6 Payroll Mistakes Canadian Trades Businesses Make Every Year

Payroll looks straightforward on the surface, but for trades businesses running crews, managing seasonal staff, and dealing with varying hours across multiple job sites, the details add up fast.

The mistakes covered here are not rare edge cases. They are the errors that show up consistently in payroll reviews across Canadian trades businesses, and each one carries a real cost.

In This Article:

• Tip #1: Misclassifying Employees as Subcontractors
• Tip #2: Miscalculating Overtime for Hourly Trades Workers
• Tip #3: Filing T4s Late or Inaccurately
• Tip #4: Missing WSIB Remittance Deadlines
• Tip #5: Skipping the Record of Employment When a Worker Leaves
• Tip #6: Not Reconciling Payroll Accounts Before Year-End
• Frequently Asked Questions

Tip #1: Misclassifying Employees as Subcontractors

Worker classification is one of the most audited areas in Canadian payroll, and trades businesses are particularly exposed. The CRA uses a multi-factor test to determine whether someone is an employee or a self-employed contractor, and paying someone as a sub does not automatically make them one.

The CRA looks at factors like who controls the work, who supplies the tools, whether the worker takes on financial risk, and whether the working relationship is exclusive.

• Control: If you set the hours, direct the day-to-day work, and determine how tasks are completed, that points toward employment.

• Tools and equipment: Employees typically use tools provided by the employer. Subs generally bring their own.

• Financial risk: True subcontractors can profit or lose money on a job. Employees cannot.

Tip #2: Miscalculating Overtime for Hourly Trades Workers

Overtime rules in Canada are set at the provincial level, not federally, which means the threshold for overtime pay varies depending on where your workers are based. In Ontario, overtime kicks in after 44 hours per week. In British Columbia, it applies after 8 hours in a day or 40 hours in a week, with double time after 12 hours in a day.

Many trades businesses apply a single, blanket overtime rule across all provinces, which creates underpayment for workers in some regions and technical non-compliance with provincial employment standards.

• Province-specific rules: Check the Employment Standards Act for each province where your workers are employed, not just where your business is registered.

• Daily versus weekly thresholds: Some provinces use both. Missing the daily threshold is a common oversight.

• Averaging agreements: Some provinces allow hours to be averaged over multiple weeks, but these require written agreements in place before the work period begins.

Tip #3: Filing T4s Late or Inaccurately

T4 slips must be issued to employees and filed with the CRA by the last day of February each year. Late filing results in penalties calculated per slip, per day, which compounds quickly for businesses with even a modest crew size.

Accuracy matters as much as timing. Errors in Box 14 (employment income), Box 22 (income tax deducted), or Box 52 (pension adjustment) can trigger CRA corrections, reassessments, or employee complaints.

• Box 40: Taxable benefits like employer-provided vehicles or tools need to be reported here. Many trades employers miss this entirely.

• Box 44: Union dues paid by employees are deductible and must be reported accurately if applicable.

• Amended T4s: If you catch an error after filing, an amended slip must be issued and re-filed with the CRA. Ignoring the mistake does not make it go away.

→ A quick tip to remember: The CRA matches T4 data against individual tax returns automatically. Discrepancies surface quickly and can lead to both employer and employee reassessments.

Tip #4: Missing WSIB Remittance Deadlines

Workplace Safety and Insurance Board premiums are a mandatory cost for most trades businesses in Ontario, and equivalent workers compensation programs exist in every other province. Missing remittance deadlines does not just result in late fees. It can affect your clearance certificate status, which is something general contractors often require before a sub can work on their site.

• Premium rate accuracy: WSIB premiums are calculated based on your industry classification and total insurable earnings. Using the wrong rate, even unintentionally, leads to arrears.

• New hire reporting: Workers must be added to your WSIB account promptly. Delayed registration creates gaps in coverage that create liability.

• Annual reconciliation: WSIB requires an annual reconciliation of estimated versus actual earnings. Skipping this creates a running balance that grows with interest.

Tip #5: Skipping the Record of Employment When a Worker Leaves

A Record of Employment must be issued within five calendar days of an employee's last day, or within five calendar days of the end of the pay period in which the interruption of earnings occurs. Failing to issue an ROE on time affects the employee's ability to apply for EI and creates a complaint risk with Service Canada.

• All separations require an ROE: Layoffs, resignations, dismissals, and even leaves of absence all trigger the requirement.

• Paper versus electronic: If you issue ROEs on paper, a copy goes to Service Canada and one to the employee. Electronic ROEs filed through the employer portal go directly to Service Canada, and you provide the employee with the confirmation number.

• Reason codes matter: Using the wrong separation code can delay or deny an employee's EI claim, which often comes back to the employer as a complaint.

Tip #6: Not Reconciling Payroll Accounts Before Year-End

Payroll reconciliation means verifying that the total wages, CPP, EI, and income tax deductions recorded in your books match exactly what was remitted to the CRA throughout the year. Leaving this until after T4s are issued creates a last-minute scramble and often surfaces discrepancies that are harder to explain the longer they sit.

• Monthly remittance matching: Every remittance payment should be reconciled against the pay periods it covers before the next one is due.

• CPP and EI maximums: Once an employee hits the annual maximum for CPP or EI contributions, deductions must stop. Continuing to deduct past the maximum is a payroll error that affects both the employer and employee.

• Year-end adjustments: Bonuses, retroactive pay, and taxable benefits paid in December need to be captured in the correct tax year, not rolled into January.

→ From a professional standpoint: A clean payroll reconciliation before year-end is the single best thing a trades business can do to make T4 season straightforward and keep the CRA from asking questions.

Frequently Asked Questions

What Happens if a Canadian Small Business Files T4s Late?

The CRA applies penalties for late T4 filing based on the number of information returns involved. For a business filing between 1 and 50 slips, the penalty is $10 per day to a maximum of $1,000 for the first failure. Repeated late filing can increase that ceiling significantly. Beyond the financial penalty, late T4s create problems for employees who need to file their personal returns on time, which often leads to direct complaints and additional CRA attention on your account.

How Do I Calculate Overtime Correctly for Trades Employees in Canada?

Overtime in Canada is governed by provincial employment standards legislation, not a single federal rule. The daily and weekly thresholds, the rate of pay for overtime hours, and the rules around averaging agreements all vary by province. A trades business operating in multiple provinces, such as one with crews in both Alberta and British Columbia, needs to apply the rules of the province where each employee actually works, not where the business is headquartered. Getting this wrong creates both wage claims and regulatory exposure.

Can Payroll Errors Trigger a CRA Review for My Business?

Yes. The CRA's payroll compliance program specifically looks for patterns like remittance shortfalls, T4 discrepancies, and misclassification of workers. A single year of errors is less likely to trigger a formal audit than a pattern across multiple years, but even isolated issues can result in a CRA contact letter requesting explanation and documentation. Correcting errors before year-end, rather than hoping they go unnoticed, is always the better approach.

Clean Payroll Is Not Optional for Trades Businesses

Payroll errors in a trades business compound quickly, across multiple employees, multiple provinces, and multiple remittance deadlines. Outline Unicorn provides fully remote payroll services to trades businesses across Canada, outside of Quebec, including T4 preparation, WSIB management, ROE filings, and year-end reconciliation. Book your complimentary 30-minute assessment at https://calendly.com/walidtimani/ and get your payroll running cleanly from the next pay period forward.