There is a persistent belief in the residential construction trades that the tax risk in cash work is the risk of being caught doing it. The record suggests something narrower and more uncomfortable: that the Canada Revenue Agency's principal method in this sector does not involve catching anyone in the act at all. It involves reading documents the contractor never saw.
Key Takeaway
The CRA has treated residential construction as a priority compliance sector since it launched its Underground Economy Initiative in 1993. Its published methods are indirect: in one project, auditors reviewed 8,396 municipal building permits and identified 2,751 unregistered building contractors, with reported collections of $4.5 million. The Agency has separately obtained Federal Court authorisation to compel a national hardware retailer to disclose commercial customer identities and annual spend. The structural exposure, however, is the Contract Payment Reporting System: a business whose income is more than 50% construction must file a T5018 slip for every Canadian-resident subcontractor paid more than $500 in the reporting period, which lets the Agency match reported subcontractor income and aggregate payments against the $30,000 GST/HST small supplier threshold. Widely repeated penalty figures for late T5018 filing conflict, and we set out below which statutory provision says what.
A Note On Currency
This article states rules, thresholds and figures as verified in August 2026, and readers should treat every number in it as needing confirmation before reliance.
Tax administration changes. Thresholds are amended, administrative policies are reissued, and enforcement priorities shift with each departmental plan. Several statistics below are drawn from CRA and Statistics Canada publications covering periods that have since closed, and we have dated each one rather than presenting them as current.
We have worked from the legislation and from CRA's own published material wherever possible, and where a figure reaches us only through secondary commentary we say so. Where sources conflict, we report the conflict rather than selecting a value, and one such conflict, on penalty amounts, is significant enough to have its own section.
This is not tax advice. It is a description of how a compliance programme has operated, written so that a business owner and their advisor can have a better-informed conversation.
Why This Sector
The Agency's attention here is neither recent nor discretionary, and understanding its age helps explain its sophistication.
CRA describes the Underground Economy Initiative as a national compliance strategy launched in 1993 to focus effort on concerns with the underground economy, defining that economy as activity that would generally be taxable if reported, and including both unreported and underreported revenues[1].
A programme running for more than three decades accumulates institutional method. The techniques described below are not improvisations; they are the product of successive multi-year plans, and CRA records that a 2004 update produced a multi-year plan containing 28 action items and pilot projects[1].
Secondary commentary identifies construction as one of three sectors CRA named in its announced focus on unreported income, alongside restaurants and retail sales[2].
The reason is not a judgment about the character of people in the trades. It is structural: residential renovation is a high-volume, low-value, consumer-facing trade in which the customer has no tax reason to want an invoice, the work is performed at a private address, and the transaction can be completed in cash without any third party observing it.
Every one of those features also describes why the Agency's countermeasures are indirect. If the transaction leaves no record between the two parties, the only available evidence sits with someone else.
How Large A Share
The sector's weight in the overall problem, reported with a conflict we cannot resolve.
One source, citing CRA estimates, states that underground economic activity accounted for more than $51.6 billion in 2016, approximately 2.5% of Canada's gross domestic product, and that residential construction accounted for 26.6% of that economy with food services at 12.1%[3]. Another commentary cites a figure of $45.6 billion without specifying the year[4]. A third states that, according to a Statistics Canada 2023 underground economy report, residential construction accounted for 32.7% of all underground economic activity[5].
We report all three and rely on none as current. The dollar figures relate to different years and the two sector shares, 26.6% and 32.7%, are attributed to different reporting periods, so they are not necessarily inconsistent; they may simply reflect a rising share over time. We were not able to verify the 2023 figure against the primary Statistics Canada release.
What the range supports is a proposition that does not depend on the precise value. Residential construction is consistently reported as the single largest identified component of Canada's underground economy, at somewhere between a quarter and a third of the total.
That matters to an individual contractor for a reason that has nothing to do with their own conduct. Enforcement resources are allocated by sector risk, so operating in this trade means operating in the sector that attracts the most attention, whether or not any particular business is doing anything wrong.
The Strategy Behind The Audit
CRA's current published approach, which explains the shape of what a contractor actually experiences.
The Agency's 2022 and forward strategy sets out three pillars: identifying underground economy activities by improving the efficiency and effectiveness of data research, analysis and third-party data collection processes; preventing such activities through early outreach and ongoing visibility; and addressing them using collaborative and tailored approaches based on the level of risk of non-compliance[6].
Two features of that document deserve a contractor's attention.
The first pillar names third-party data collection as a core method, which is the formal statement of everything described in the next three sections. The Agency is telling the public that its identification strategy relies on obtaining records from parties other than the taxpayer.
The second is the graduation of response. CRA states that it reserves full audit interventions such as net worth analysis to target and address cases with the highest level of non-compliance, and describes adopting an approach intended to ensure the most appropriate intervention is applied to the level of risk without causing unnecessary burden[6].
The practical reading is that most contacts are not full audits. A letter, a questionnaire, a books and records review or a community visit are lower-intensity interventions, and CRA has separately described conducting books and records reviews and community visits as part of its outreach programmes[1].
The corollary is the part contractors underestimate. If net worth analysis is reserved for the highest-risk files, then a taxpayer who receives one has already been assessed as high risk, and the tone of the engagement is set before the first meeting.
The Permit Project
The method that gives this article its title, and the clearest illustration of how identification works.
Secondary commentary describes a project in which CRA auditors obtained lists of municipal building permits in some communities in order to check worksites for unregistered building subcontractors. It reports that a review of 8,396 building permits identified 2,751 unregistered building contractors, and that the resulting audit and enforcement activity produced income tax collections of $4.5 million[2].
We report these figures as stated by that source, which is a Canadian tax law practice, and note we could not locate the underlying CRA project report to verify them independently.
The mechanism is worth understanding because it is entirely lawful, requires no suspicion of any individual, and is difficult to defeat.
A building permit is a municipal public record. It identifies a property, a scope of work, a valuation and frequently a contractor. It exists because the homeowner wanted the work to be legal, inspected and insurable, which are motivations wholly unrelated to tax.
So the permit file is a list of construction projects that occurred, with values attached, generated by a party with no interest in concealment. Matching that list against registrations and filings identifies businesses that performed work and do not appear in the tax system.
A ratio of roughly one unregistered contractor identified per three permits reviewed, if the reported figures are accurate, is a remarkably productive yield for a data-matching exercise, and it explains why the method persists.
The Hardware Store Order
The second identification method, and the one with the widest reach.
Commentary reports that in July of the relevant year CRA obtained a Federal Court order compelling a national hardware retailer to disclose the identities of the chain's commercial customers, together with the total annual amount spent by those customers at its stores across the country, for the period from January 2013 to December 2016[3].
We report that as the source states it and have not reviewed the court order.
Consider what that data set contains. A commercial account at a building supply retailer identifies a business, and the annual spend figure is a measure of materials purchased.
Materials purchased is a proxy for work performed. A contractor who bought a quantity of lumber, drywall and fixtures in a year performed a volume of work broadly proportional to it, and that volume implies revenue.
So a materials figure obtained from a third party can be compared against reported revenue, and a substantial mismatch is a selection criterion. The contractor never filed the record that identified them, and could not have known it existed in that form.
The generalisable point for any trade is that purchases leave a record even when sales do not. A business that deals in cash on the revenue side rarely does so on the supply side, because suppliers extend credit, offer trade pricing and require accounts.
The Unnamed Persons Power
The statutory basis for that order, stated carefully because the detail matters.
The Income Tax Act contains a requirement power allowing the Minister to compel information from a person. Where the information sought concerns unnamed persons, the Minister must obtain judicial authorisation, which is why the retailer disclosure was reported as proceeding by way of a Federal Court order rather than a simple demand[3].
We have not reproduced the provision's text or its conditions here, and a business facing such a matter should obtain advice on the current wording, which has been amended over time.
The practical significance for a contractor is the following. The Agency does not need to suspect a particular business in order to obtain records about a class of businesses. It needs to satisfy a court in respect of a described group, and the resulting data then identifies individuals within it.
That inverts an assumption most taxpayers hold, which is that scrutiny follows suspicion. In this programme, the data comes first and the suspicion is generated from it.
It also means that the relevant question for a contractor is not whether they have attracted attention. It is whether their reported figures would look consistent alongside third-party records they will never see.
The Slip Somebody Else Files
The structural mechanism, and the one that operates continuously rather than by project.
The Contract Payment Reporting System requires businesses in the construction sector to report payments made to subcontractors. Commentary describes the matching consequence directly: if a payment is entered and the recipient does not report the income, the Agency identifies the discrepancy, and a construction business that never reports any subcontractor payments can itself attract closer examination[4].
One practitioner source identifies the filing obligation as arising under the Income Tax Regulations[7].
The design is elegant from an administrative standpoint and uncomfortable from a contractor's. It conscripts the general contractor into reporting on the subcontractor, at no cost to the Agency, on a recurring annual basis, across the entire sector.
And it produces two independent signals rather than one. A slip filed against a business number that reports no corresponding income is a direct mismatch. A construction business that files no slips at all is an anomaly, because subcontracting is near-universal in the trade.
The second signal is the one that catches businesses who believe non-participation is safety. Filing nothing is itself a data point.
T5018 Mechanics
The rules a contractor must actually operate, assembled from practitioner sources and stated with the qualifications each requires.
Who files. Sources consistently describe a threshold test based on the proportion of business income derived from construction, expressed as more than 50% of business income for the reporting period[7][8][9].
The $500 threshold. Payments to a subcontractor totalling less than $500 in the reporting period are described as not requiring a slip[9][10]. Two sources state that the threshold is measured on payments before GST/HST, while the amount reported on the slip itself is the gross figure including those taxes[8][11]. That asymmetry is easy to get wrong in both directions.
Aggregation. The threshold applies to total payments to each subcontractor during the period rather than to individual invoices[12], which means a series of small payments can cross it.
Who is a subcontractor. Sources describe the requirement as applying to Canadian-resident recipients whether they operate as an individual, partnership, trust or corporation[8][9]. Payments to non-residents are described as reportable instead on a different return[10][9].
What is not reportable. Employee wages belong on employment slips rather than here[13], and one source states that payments for services such as bookkeeping, janitorial services or legal fees are not reportable[9], the obligation attaching to construction services.
Mixed invoices. One source states that where the services component clears the threshold, the full invoice amount is reportable including materials[11], and another that payments for mixed contracts including both labour and materials are reportable[12].
The deadline. Six months after the end of the reporting period the filer selects, so a December year end produces a June 30 deadline and a September 30 year end a March 31 deadline[8][11]. This is not a fixed calendar date across all filers, which is a common source of error.
Electronic filing. One source states that since 1 January 2024 electronic filing is required once six or more slips of a single type are produced, and that paper filing above that threshold triggers a separate penalty[7][11].
The Aggregation Effect
The consequence most contractors have never had explained to them, and the reason the system exists in this form.
Sources describe the mechanism plainly. A supplier of services is generally not required to register for GST/HST while below a $30,000 revenue threshold. Any individual job may fall well below that figure, but several jobs in aggregate may exceed it. By totalling a subcontractor's slips, the Agency can determine whether an individual has crossed the threshold and should be registered, collecting and remitting[10][9].
This is the point at which the reporting system stops being an income-matching tool and becomes a registration-detection tool.
A subcontractor working for five general contractors may be beneath the threshold in the view of each of them individually, and none of the five has any way of knowing about the other four. The Agency is the only party that sees the sum.
The exposure that creates is asymmetric and worth stating carefully. A subcontractor who ought to have registered and did not has an unremitted tax liability calculated on their sales, and it does not disappear because they never charged it. The obligation to remit is not conditional on having collected.
For a general contractor the related risk is different: a subcontractor who was not registered but should have been, and who charged and was paid amounts described as tax, raises input tax credit questions on the payer's side.
The defensive practice both parties can adopt is the same one, and it is trivially cheap: obtain and record the subcontractor's registration number, and verify it, before the first payment.
A Penalty Figure Worth Correcting
A conflict across sources that we can resolve against the legislation, which is unusual enough to be worth setting out at length.
Several practitioner and commercial sources state that the late filing penalty for these slips is $25 per day, with a minimum of $100 and a maximum of $2,500[12][14][15]. One source expressly disputes that characterisation, describing the penalty as graduated by the number of slips and the number of days late, running at $10 per day to a maximum of $1,000 for filers of fewer than 50 slips with a $100 minimum, and scaling upward for larger filers, and stating that the $2,500 figure is a per-return maximum for one tier rather than a per-slip charge[7].
The legislation supports the second account for prescribed information returns.
Subsection 162(7) of the Income Tax Act imposes, for failures to which no other penalty provision applies, a penalty equal to the greater of $100 and $25 multiplied by the number of days, not exceeding 100, during which the failure continues[16]. That is the source of the widely quoted $2,500 maximum.
Subsection 162(7.01) then provides a separate rule for information returns of a type prescribed for its purpose, imposing a penalty equal to the greater of $100 and, where the number of those returns is fewer than 51, $10 multiplied by the number of days not exceeding 100; where the number is greater than 50 and fewer than 501, $15 multiplied by the number of days not exceeding 100; with further tiers above that[16].
The legislative history confirms the purpose. A Canada Gazette explanation records that because each slip is a separate information return, the general rule could produce extreme results for large filers, and that Budget 2009 announced a separate, less severe graduated penalty for prescribed information returns, enacted in the implementing legislation that received Royal Assent in March 2009[17].
So the two figures are not competing accounts of one rule. They are two different provisions, and which applies turns on whether the return is prescribed for the purpose of the graduated rule.
We were not able to verify from the sources available whether these particular construction slips appear on the prescribed list, and we therefore do not assert which provision governs them. What a contractor should take from this is narrower and still useful: the $25 per day, $2,500 maximum figure circulating in commentary is the general rule, a graduated alternative exists for prescribed returns, and the difference is material. Confirm which applies before relying on either.
When The Clock Stops
An administrative interpretation with a consequence that surprises filers.
A published CRA technical interpretation addresses how the graduated penalty is calculated where slips of the same type are filed late at different times. It states that the calculation is made on the number of days during which the failure continues, being the number of days after the deadline until all required slips of that type are filed, so that the failure to file continues until all the required slips have been filed. The consequence is that a person filing slips of the same type late but at different times is liable to a penalty based on the total number of slips filed late and on the number of days until the last slip was filed[18].
The example discussed involves a filer who submitted a further single slip well after the deadline, with the penalty tier determined by the total count[18].
Two practical consequences follow, and they are our own reading.
Partial filing does not stop the clock. A contractor who files most slips on time and one subcontractor's slip three months later has not limited exposure to that one slip; on this interpretation the failure continued until the last one arrived.
And the count that sets the tier is the number filed late in total. Discovering a missed subcontractor after filing therefore has a different character from discovering one before filing, which is an argument for completing the subcontractor list before submitting anything rather than filing what is ready and following up.
Net Worth Assessment
The technique reserved for the most serious files, and the reason it is feared.
CRA's published strategy states that it reserves full audit interventions such as net worth analysis to target and address cases with the highest level of non-compliance[6].
The method is indirect verification. Rather than auditing revenue records that may be incomplete or absent, the auditor measures the change in a taxpayer's assets and liabilities over a period, adds estimated personal expenditures, and treats the total as income that must be accounted for.
Its significance for a residential contractor is that it does not require the Agency to find the unreported sales. It requires only that the taxpayer's wealth and spending exceed what their reported income could support.
That reverses the practical burden in a way taxpayers find disorienting. The auditor is not proving that a particular job was unreported; they are producing a figure the taxpayer must explain, and explanations require records.
Legitimate non-income sources of funds exist in abundance: gifts, inheritances, loan proceeds, sale of personal property, funds brought from outside Canada, accumulated savings. Each is a complete answer, and each requires documentation that families frequently do not keep.
We would state the practical implication for any owner-managed business in this sector plainly. If a substantial personal transaction ever occurred without paperwork, the paperwork is worth creating contemporaneously now rather than reconstructing under assessment later.
The Scale Of The Programme
The resourcing, from CRA's own internal audit reporting, which gives a sense of proportion.
A CRA internal audit report on the Underground Economy Initiative records that for the fiscal year ended 31 March 2008, the Compliance Programs Branch dedicated 1,028 audit full-time equivalents to the initiative, and that 11,394 underground economy cases consisting of 17,273 audits were completed in the period, resulting in approximately $575 million in unreported income and $150 million in taxes assessed[19].
Those figures are from a fiscal year that closed a long time ago and we present them as historical rather than current.
Two ratios in them are nonetheless instructive and are our own calculation from the reported figures.
Roughly 1.5 audits per case suggests that identifying one non-compliant taxpayer frequently produces more than one audit, which is consistent with a related party, a corporation and its shareholder, or a chain of subcontractors being examined together.
And $150 million assessed against $575 million of unreported income implies an effective rate of roughly 26% across the programme, which is a reminder that the assessment is tax on the unreported amount rather than the amount itself, before any penalties and interest.
Separately, commentary describes an underground economy project in which CRA investigated almost 6,600 building contractors and found over 1,200 who had failed to file a return at least once in the period from 2008 to 2012[2]. We report that as stated and could not verify it independently.
The proportion, roughly one in five of those examined having at least one unfiled year, indicates that non-filing rather than misreporting is a substantial part of what these projects find.
What The Auditor Actually Examines
Moving from identification to the audit itself. This section is our own analysis, informed by the mechanisms above rather than drawn from a single source.
Once a residential construction file is selected, the examination tends to concentrate on a small number of areas where the sector's economics and its records diverge.
The revenue reconciliation. Deposits to all accounts, business and personal, compared against reported sales. Unexplained deposits are the most common starting point because they are simple to identify and require the taxpayer to explain each one.
Materials against revenue. The relationship described in the hardware store section, applied internally. A gross margin materially out of line with sector norms, or with the taxpayer's own prior years, invites the question of what was built with materials that produced no sale.
Work in progress and holdbacks. Construction contracts create timing differences between work performed, amounts billed and amounts received. These are legitimate and they are also where revenue can be deferred beyond what the facts support, so an auditor will test the cut-off.
Personal use. Vehicles, tools, fuel, and materials consumed on the owner's own property. This is not usually the largest adjustment and it is frequently the easiest for an auditor to sustain, because the records to rebut it rarely exist.
Subcontractor payments. Both directions. Whether amounts claimed as subcontract costs were paid to real parties for real work, and whether the corresponding slips were filed.
The last of those carries a specific risk. A deduction claimed for a payment to a subcontractor who cannot be located, who denies receiving it, or for whom no slip was filed, is a deduction under pressure, and the consequence falls on the payer.
The GST/HST Exposure Runs Parallel
A structural feature of any indirect audit in this sector that contractors consistently underestimate.
Unreported revenue in a registered business is not one exposure. It is two, because the same sales carry both income tax and, where the supply is taxable, GST/HST.
The two liabilities are assessed under different statutes with different limitation rules and different penalty and interest regimes, and an adjustment on one side does not automatically produce a matching adjustment on the other; each is assessed on its own basis.
For a contractor the arithmetic consequence is that the total assessed liability arising from an amount of unreported revenue commonly exceeds what a marginal income tax rate alone would suggest.
There is a further wrinkle specific to residential work. Certain supplies relating to residential property carry particular treatment, and self-supply and change-in-use rules can create liabilities on transactions that never involved a sale to a third party at all.
This publication has addressed self-assessment on new residential construction separately, and the point to carry here is narrower: a contractor who builds or substantially renovates residential property, including for their own account, should not assume that the absence of a sale means the absence of a GST/HST event.
That is a question for an advisor on specific facts, and the reason to raise it in an audit article is that it is a common source of assessments that the taxpayer did not anticipate at all.
The Subcontractor Status Question
The adjacent exposure that frequently emerges from the same audit.
A construction business that treats workers as subcontractors, files slips accordingly, and withholds nothing, is making a characterisation that CRA can examine. Where the Agency concludes that a worker was in substance an employee, the consequences fall on the payer and are not limited to the tax.
They include amounts that should have been withheld and remitted, both the employee and employer portions of statutory contributions, penalties and interest, and potential director liability for unremitted source deductions.
This publication has treated the reclassification analysis and director liability for source deductions separately, and we do not repeat the legal tests here.
The reason it belongs in an audit article is that the two exposures are discovered together. An auditor examining subcontractor payments for the purpose of verifying deductions and slip filing is examining the same population of relationships that the status question turns on, and the file naturally raises both.
The practical implication for a contractor is that the T5018 exercise and the worker status question should not be handled as separate compliance matters by different people at different times. They concern the same list of names.
What Records Survive
The documentation position, framed by what the mechanisms above actually test. This section is our own analysis.
The recurring feature of every method described in this article is that CRA arrives holding a third-party record and asks the taxpayer to reconcile to it. That determines what documentation is worth keeping.
A complete job list. Every project, with address, date, customer, contract value and amount received. This is the record that reconciles to a permit file, and its absence is itself an adverse finding.
Supplier statements retained, not just receipts. Annual statements from building supply accounts are the counterpart to the data a retailer would disclose, and a contractor who holds their own copy can reconcile rather than dispute.
Subcontractor information collected before payment. Legal name, business number or social insurance number, address, and registration status. One source describes contractors who avoid difficulty as those who collect a completed information sheet from every subcontractor before the first cheque clears[7].
Deposit explanations, contemporaneously. Any non-revenue deposit to any account, business or personal, annotated at the time with its source. A loan advance, a gift, a transfer between the owner's own accounts and a repayment all look identical in a bank statement three years later.
Personal-use apportionment records. Vehicle logs and materials taken to the owner's own property, recorded as they occur.
Sources make the related point about the SIN and business number requirement: a penalty may apply for failing to obtain identification numbers, and may be waived where the filer can demonstrate a reasonable effort to obtain them[12]. Demonstrating a reasonable effort requires evidence that the effort was made, which means a record of the request.
Before The Auditor Arrives
The relief mechanism, described carefully because its availability is conditional and its terms have changed.
Commentary states that taxpayers with unreported income, unreported GST/HST or unfiled returns can submit a voluntary disclosure, and that where an application is made before CRA targets the taxpayer, the described outcomes include no prosecution, no civil penalties, and in some cases interest relief[2].
We report that as the source, a tax law practice, describes it, and we flag several qualifications strongly.
The programme's terms and conditions have been revised more than once, and the relief available has been narrowed over time and differentiated by the nature of the disclosure. A description of outcomes written at one point may not describe the programme as it currently operates.
The central condition, however, is structural and has been constant in character: the disclosure must be voluntary, which means made before the Agency has initiated action in respect of the matter.
That condition is what makes every identification method described in this article time-sensitive. A permit review, a third-party data order or a slip mismatch that has already reached a taxpayer's file may extinguish voluntariness before the taxpayer knows anything has happened.
The practical instruction is that if a contractor is considering a disclosure, the decision has a deadline they cannot observe, and the only sensible response is to obtain advice promptly rather than deliberating. Any such application should be made with professional representation and on current programme terms rather than on a description of how it once worked.
What To Do
Assume the Agency can obtain a materials figure. Purchases leave records even when sales do not, and reported revenue that cannot support the materials bought is a selection criterion.
Keep a complete job list reconcilable to permits. Address, date, value, amount received. It is the record a permit-based review tests against.
Collect subcontractor identification before the first payment. Legal name, business or social insurance number, address, registration status, with a record of the request itself so a reasonable-effort defence exists.
Verify GST/HST registration numbers. Aggregate slips are how the Agency detects unregistered suppliers, and the exposure runs in both directions.
Apply the threshold correctly. Measured on cumulative payments to each subcontractor before tax, while the amount reported on the slip is the gross figure including it.
Complete the subcontractor list before filing anything. On CRA's published interpretation, the failure continues until the last slip of that type is filed, so partial filing does not limit exposure.
Diarise the deadline from your own period end. Six months after the reporting period you selected, not a fixed calendar date shared with other filers.
Confirm which penalty provision applies before relying on a figure. The general rule and the graduated rule for prescribed returns produce materially different numbers.
Annotate every non-revenue deposit when it happens. This is the only defence to an indirect verification method that works, and it cannot be reconstructed convincingly years later.
Treat worker status and slip filing as one exercise. They concern the same list of people and are discovered in the same audit.
The Limits Of This Analysis
Several caveats matter and readers should weigh them before relying on anything here. This article is not tax or legal advice and no reader should act on it without professional guidance on their own facts. Every threshold, rate and figure is stated as verified in August 2026 and requires confirmation before reliance, since tax administration changes. The statutory penalty provisions are quoted from a published consolidation of the Income Tax Act; we set out the difference between the general and graduated rules and expressly did not determine which governs these particular slips, which readers must confirm. Several operational figures, including the permit project counts, the contractor investigation counts and the collections figure, reach us through a Canadian tax law practice's commentary and we could not locate the underlying CRA project reports to verify them. The court order compelling retailer disclosure is reported at second hand and we have not reviewed the order. Underground economy dollar figures and sector shares conflict across sources and relate to different periods; we have reported the range and rely on none as current, and could not verify the most recent sector share against the primary statistical release. CRA programme statistics are drawn from a fiscal year that closed long ago and are presented as historical. T5018 mechanics are assembled from practitioner and commercial publications rather than from the Regulations directly, and those sources conflict on penalties as discussed. The voluntary disclosure description reflects a commentary account of a programme whose terms have been revised. The audit examination areas, the record-keeping analysis, the ratio calculations from reported programme figures and the observations on aggregation exposure are our own analysis. This article does not address provincial sales tax, workers compensation, licensing, holdback and lien legislation, or the detailed legal tests for worker status, several of which this publication treats separately.
Frequently Asked Questions
How does CRA identify contractors it has never heard of?
What is the T5018 actually for?
Is the penalty really $25 a day to a maximum of $2,500?
If I file most slips on time, is my exposure limited to the late ones?
What is a net worth assessment and why does it matter here?
What single record matters most?
References
- Canada Revenue Agency. Underground Economy Initiative Internal Audit, Final Report, Corporate Audit and Evaluation Branch, December 2008, on the initiative as a national compliance strategy launched in 1993, the definition of the underground economy as activity that would generally be taxable if reported including unreported and underreported revenues, the 2004 update to a multi-year plan containing 28 action items and pilot projects, and the conduct of books and records reviews and community visits as part of outreach. Note: a CRA primary publication reporting on a period that has since closed. canada.ca — UEI Internal Audit 2008
- Canadian tax law practice commentary. CRA Tax Audit: Building Contractors and Unreported Income, on the building sector as one of three named sectors alongside restaurants and retail, the project obtaining municipal building permit lists with 8,396 permits reviewed and 2,751 unregistered contractors identified producing $4.5 million in collections, the investigation of almost 6,600 building contractors with over 1,200 having failed to file at least once between 2008 and 2012, and the description of voluntary disclosure outcomes. Note: a law firm marketing publication; we could not locate the underlying CRA project reports to verify these figures. canadiantaxamnesty.ca
- Feigenbaum Consulting. CRA Targeting Contractors Buying Supplies at Hardware Stores in New Audit, on CRA estimates of underground activity exceeding $51.6 billion in 2016 at approximately 2.5% of GDP, with residential construction at 26.6% and food services at 12.1%, and on the Federal Court order compelling a national hardware retailer to disclose commercial customer identities and total annual spend for January 2013 to December 2016. Note: a professional services commentary; the court order was not reviewed by us. feigenbaumlaw.com
- QuickBooks Canada. Tax Compliance: How the CRA Is Unearthing the Underground Economy, on the Contract Payment Reporting System and the matching consequence where a reported payment does not correspond to reported income, on a construction business reporting no payments attracting closer examination, and citing an underground economy figure of $45.6 billion. Note: a commercial publication; the figure is undated in the source. quickbooks.intuit.com
- Invoice Data Extraction. T5018 Statement of Contract Payments: Compile-and-File Workflow, citing a Statistics Canada 2023 underground economy report for residential construction accounting for 32.7% of underground economic activity, and on the 50% construction-income test, the $500 threshold measured before tax, gross-inclusive slip reporting, and the six-month deadline anchored to the chosen period end. Note: a commercial publication; we could not verify the statistical figure against the primary release. invoicedataextraction.com
- Canada Revenue Agency. 2022+ Underground Economy Strategy, on the three pillars of identifying activities through data research, analysis and third-party data collection, preventing activities through early outreach and ongoing visibility, and addressing activities using collaborative and tailored approaches based on risk; and on reserving full audit interventions such as net worth analysis for cases with the highest level of non-compliance. Note: a CRA primary publication. canada.ca — 2022+ UE Strategy
- Insight Accounting CPA. T5018 Contractor Payment Information Return Canada 2026, on the 50% test and $500 threshold excluding GST/HST, the six-month deadline, mandatory electronic filing from 1 January 2024 once six or more slips of a type are produced with a separate penalty for paper filing above that, the identification of the obligation with Income Tax Regulations s.238 and the Contract Payment Reporting System, the graduated penalty description, the express dispute of the $2,500 per slip characterisation, and the practice of collecting a subcontractor information sheet before the first payment. Note: a professional services publication. insightscpa.ca
- SKG Financial. T5018 Filing Guide for Ontario Contractors (2026), on the 50% test, the $500 threshold measured before GST/HST with the slip amount reported inclusive, application to corporations, partnerships and sole proprietors, and the six-month deadline with worked examples. Note: a professional services publication. skgfinancial.com
- Olympia Benefits. T5018 Guide: Contractor Payments for the Construction Sector, on the more-than-half test, reporting of all amounts paid to subcontractors including individuals, partnerships, corporations and trusts, the non-resident alternative return, the exclusion of services such as bookkeeping, janitorial and legal fees, and the use of aggregated slips to determine whether a contractor exceeded the $30,000 registration threshold. Note: a commercial publication. olympiabenefits.com
- TaxPage. T5018 Statement of Contract Payments: Toronto Tax Lawyer Analysis, on the non-resident alternative return, the below-$500 exemption with voluntary completion permitted, and the explanation that individual jobs may fall below the registration threshold while several in aggregate exceed it, allowing better identification of those required to register. Note: a law firm publication. taxpage.com
- Invoice Data Extraction, as above, on gross-inclusive reporting, the payments-not-billings test, mixed services-and-materials invoices being reportable in full where the services component clears the threshold, and the deadline anchored to period end rather than a fixed calendar date. invoicedataextraction.com
- WelcomeAide. How to Complete T5018 for Contract Payments, on the threshold applying to total payments per subcontractor in the period, the requirement to provide a copy to the subcontractor, reporting of mixed labour and materials contracts, the penalty for failing to obtain identification numbers with waiver on demonstrated reasonable effort, and a stated late filing penalty figure. Note: a commercial publication; its penalty figure conflicts with other sources as discussed in the text. welcomeaide.com
- Wealthsimple. Everything You Need to Know About the T5018, on excluding payments below $500 and on employee wages belonging on employment slips rather than contract payment slips. Note: a commercial publication; its penalty description conflicts with other sources. wealthsimple.com
- Shajani CPA. T5018 Compliance Made Easy, on the $500 threshold with worked examples and on a stated daily penalty and maximum. Note: a professional services publication; the penalty figure conflicts with other sources as discussed. shajani.ca
- PiggyBank. What Is the T5018 Form, on the requirement to file for each directly engaged subcontractor and on the summary return, and on a stated daily penalty and maximum. Note: a consumer finance publication; the penalty figure conflicts with other sources. piggybank.ca
- Department of Justice Canada. Income Tax Act, RSC 1985, c. 1 (5th Supp.), section 162, consolidated text, for subsection 162(7) imposing a penalty equal to the greater of $100 and $25 multiplied by the number of days not exceeding 100 during which the failure continues, and subsection 162(7.01) imposing, for information returns of a type prescribed for its purpose, a penalty equal to the greater of $100 and $10 per day where the number is fewer than 51, $15 per day where greater than 50 and fewer than 501, with further tiers. Note: primary legislation as published in the consolidation. laws-lois.justice.gc.ca — ITA s.162
- Canada Gazette Part II. Regulations Amending the Income Tax Regulations (Late Filing Penalty, Prescribed Information Returns), on each individual slip being a separate information return, the resulting severity of the general penalty for large filers, the Budget 2009 announcement of a separate less severe graduated penalty for prescribed information returns, and its enactment in the Budget Implementation Act, 2009, which received Royal Assent on 12 March 2009. Note: primary regulatory publication. gazette.gc.ca
- Canada Revenue Agency technical interpretation 2018-0748441I7, as reproduced by a tax information service, on the subsection 162(7.01) penalty being calculated on the number of days during which the failure continues, meaning until all required slips of the same type are filed, so that a person filing slips of the same type late at different times is liable based on the total number filed late and the number of days until the last slip was filed. Note: accessed through a secondary reproduction rather than from CRA directly. videotax.com
- Canada Revenue Agency, Underground Economy Initiative Internal Audit, as above, for the fiscal year ended 31 March 2008 figures of 1,028 audit full-time equivalents dedicated to the initiative, 11,394 underground economy cases consisting of 17,273 audits completed, approximately $575 million in unreported income and $150 million in taxes assessed. Note: historical figures from a closed fiscal year. canada.ca — UEI Internal Audit 2008
This article is provided for general informational purposes and is not tax or legal advice. Thresholds, rates and administrative positions are stated as verified in August 2026 and change over time. Several operational statistics are reported at second hand from professional commentary and could not be independently verified; conflicting figures are reported rather than resolved. No reader should act on this article without professional guidance on their own facts.