Ontario contractor year-end checklist for 2026

Short answer: an Ontario contractor's year-end checklist comes down to five things to line up before December 31: T4 slips (due the last day of February), T5018 slips for subs (due six months after your reporting period ends), WSIB clearances and reconciliation, HST receipts that back up your input tax credits, and a list of open contracts for the 2027 holdback change.

This checklist is for owner-run construction businesses in Ontario with a December 31 calendar year, people on payroll and subcontractors on the books. If your corporation has a different fiscal year-end, some dates below move with it.

Checked against CRA, WSIB, Government of Ontario and Legislative Assembly of Ontario pages on November 11, 2026. This is general information, not legal or tax advice; confirm with your accountant or lawyer.

Ontario contractor year-end dates at a glance

Swipe the table sideways to see every column.

Payroll: T4 slips and the T4 Summary

CRA's page on when to file information returns says the T4 filing due date is "the last day of February after the preceding calendar year." For 2026 pay, that is the end of February 2027.

The last day of February 2027 is a Sunday. CRA says a return due on a Saturday, Sunday or public holiday is on time if CRA receives it, or it is postmarked, by the next business day. Don't plan around that; finish slips the week before.

What to do in December: confirm every employee's address and social insurance number are on file and current. Match pay records to what was actually paid, including people who left mid-season. When someone stops working for you because of a layoff, retirement, resignation or dismissal, CRA suggests you work out their year-to-date earnings and give them a slip.

Subcontractors: T5018 slips

A T5018 is CRA's Statement of Contract Payments: the slip a construction business files to report what it paid each subcontractor for the period. CRA's T5018 page says businesses must report contract payments if more than 50% of their business income comes from construction activities. You report payments to Canadian-resident subcontractors when the total paid to that sub for the period is more than $500, not counting GST/HST. Payments for goods only are not reported.

The return is due six months after the end of the reporting period you chose, which can be the calendar year or your fiscal period. For a calendar-year filer, 2026 payments are due by June 30, 2027.

The deadline is far off. The paperwork is not. For each sub, CRA wants the business name and address, either their 15-character program account number or their SIN, and the total you paid. Treat every SIN, your crew's and your subs', as sensitive: collect it only for payroll and the slips, keep it where only you or your bookkeeper can see it, and never ask for one by text or in the crew group chat. The easiest time to get a missing business number is before you pay the sub's last invoice of the year, not in June when nobody is answering the phone.

WSIB: clearances, 2027 rates and reconciliation

Clearances

A WSIB clearance is a number WSIB issues to registered businesses that are up to date on premiums and reporting. It is valid for up to 90 days. If you hire subs, check that each one's clearance is current before they start, and check again on long jobs: one you checked in August has expired by December.

The reason it matters: under WSIB's construction clearance policy, if you hire a sub without a valid clearance, you may be liable for what that sub owes WSIB, up to the labour portion of the contract. A valid clearance relieves you of that liability for the period it covers. Ask WSIB or your accountant how that applies to your subs.

2027 premium rates

WSIB says 2027 rate statements are available only online, starting in November, through a WSIB online services account. Look yours up now. It is part of your loaded labour cost for next year, so it belongs in your 2027 price sheet before the first spring quote goes out.

Reconciliation

WSIB's reconciliation page says businesses that reported and paid premiums monthly, or closed an account during the year, must reconcile, and that reconciliations are due March 31 each year. If you report annually or quarterly, WSIB says you don't need to reconcile. Reconciling confirms you reported the right amount in premiums. Pull your 2026 insurable earnings by worker now, while the season is fresh, so March is a check rather than a dig.

HST: receipts and input tax credits

Ontario's HST rate is 13% (CRA's GST/HST rate page). If you are a GST/HST registrant, input tax credits (ITCs) let you recover the HST you paid on purchases and expenses used in your commercial activities.

The catch is paperwork. CRA says you need sufficient documentary evidence before you claim an ITC, and what counts depends on the amount. Every invoice or receipt needs the supplier's name, the invoice date and the total paid. From $100, it also needs the supplier's GST/HST registration number and the HST charged, or a note that the price includes HST. From $500, it also needs your name or business name, a brief description of what you bought and the payment terms. A faded till receipt for a $640 load of pavers that doesn't show the yard's GST/HST number or your business name may not meet that bar, so ask the yard for a proper invoice.

For most registrants, CRA allows four years to claim an ITC, so a receipt you missed this spring can usually still be claimed. CRA sets a two-year limit for listed financial institutions and some businesses over a $6 million threshold, so ask your accountant before you claim a missed ITC on a later return. In December, match every job's receipts to the reporting period they belong to, and chase missing invoices while suppliers still remember the order.

Construction Act: the holdback change coming in 2027

Holdback rules sit in Ontario's Construction Act. In an October 27, 2026 backgrounder, the Ontario government describes a holdback as the 10 per cent that contractors and subcontractors withhold from the cost of services or materials supplied on a project, so that enough money is available to pay any lien claims. The same document says that starting January 1, 2027, project owners will be required to release holdbacks annually on the anniversary date of each contract.

A DLA Piper summary of the amendments says the annual-release rules came into force on January 1, 2026, with transition rules: for contracts signed after that date, the first release follows the contract's first anniversary, and for older contracts it follows the second anniversary after January 1, 2026. Either way, the first required releases fall in 2027, and the rule mostly matters for contracts that run longer than a year.

That backgrounder also introduces the proposed Building Ontario Faster Act, 2026 (Bill 140). If passed, it would let the Attorney General make regulations allowing owners named in those regulations to release holdback for all their contracts on one date they choose, instead of each contract's anniversary. The province says the regulation would apply to Ministry of Transportation projects, and other public and private owners could ask to be included. As of this writing, Bill 140 has passed second reading and been sent to committee; it is a proposal, not law.

What to do now: list every open contract with its signing date, contract value and the holdback held or owed on both sides, meaning what you hold back from your subs and what your customer holds back from you. You need that list whichever version applies. How the rules apply to contracts signed before 2026, and to your own contracts, is a question for a construction lawyer.

Records: what to keep and for how long

CRA's record-keeping page says businesses generally must keep required records and supporting documents for six years from the end of the last tax year they relate to. They must be kept at your place of business or residence in Canada unless CRA gives you written permission otherwise, and CRA says records stored outside Canada but accessed electronically from inside Canada don't count as kept in Canada. If your records live in software, ask the vendor where the data is stored, and ask your accountant whether that setup works for you.

The practical version is one folder per job, paper or digital, holding the signed quote, change orders, invoices, receipts, crew hours and photos. When CRA, WSIB, a customer or a lawyer asks about a job from three years ago, you open one folder instead of four shoeboxes.

The job-by-job review that's yours to do

Everything above keeps you in good standing. None of it tells you whether 2026 was a good year, job by job. Block out one evening in December for four questions.

Which jobs made money?

For each finished job, take the invoiced revenue and subtract labour, materials, equipment, subs, delivery and disposal. Then rank the jobs by margin. Example numbers, not industry averages: a $20,000 patio with $15,000 in job costs made $5,000, a 25% margin. A $12,000 walkway that took twice the planned crew-days might have made $1,200, or 10%. Our job costing guide walks through the method on paper or in a spreadsheet.

Which quotes are still open?

Fall quotes go quiet in November. List every quote that went out but wasn't accepted, with the customer, the scope and the date, and put a January follow-up in the calendar. "Call me in spring" means nothing if nobody calls.

What will you charge in 2027?

Your 2027 WSIB rate, any raises for returning crew and this season's real job costs all feed next year's price sheet. For interlock and hardscape work, our guide to pricing interlock jobs builds rates from your own job history.

Who is coming back?

Know which crew members are returning in spring, at what rate, and which spots you need to fill.

The printable year-end checklist

• Payroll: confirm addresses and SINs, reconcile 2026 pay records and give slips to people who left. T4s are due the last day of February 2027 (CRA).
• Subs: collect business names, addresses and program account numbers or SINs, keep SINs where only you or your bookkeeper can see them, and total 2026 payments per sub. T5018 is due June 30, 2027 for calendar-year filers (CRA).
• WSIB clearances: check that every sub's clearance is current before they start; each is valid for up to 90 days, and without one you may be liable for what the sub owes WSIB (WSIB).
• WSIB rates and reconciliation: look up your 2027 rate statement and pull 2026 insurable earnings. Reconciliation is due March 31, 2027 if you reported monthly or closed an account in 2026 (WSIB).
• HST: match receipts to reporting periods, get proper invoices (the supplier's GST/HST number from $100; your name, a description and payment terms from $500) and list unclaimed ITCs (CRA).
• Holdback: list open contracts with signing dates and holdback on both sides, and ask a construction lawyer about 2027 (Ontario).
• Records: one folder per job, kept for six years from the end of the last tax year they relate to (CRA).
• Business review: rank 2026 jobs by margin, list open quotes for January, update the 2027 price sheet and confirm returning crew.

Where our software fits, and where it doesn't

We make software, and this section and the closing one are about it. NexusCRM by NexusAI GTA is the CRM for contractor crews, built in Toronto.

When a customer accepts a quote online, the invoice, the job and the schedule follow from it without retyping, so the signed quote, the invoice and the job stay together. On Pro and Elite, labour and receipts land on each job's live P&L, and crew pay and commissions are worked out in the system, with four crew pay models: hourly, per-day, per-project and per-linear-foot. Every change is recorded in an audit log, and NexusCRM is HST-native.

Where the data lives: every client gets a dedicated private instance with its own database, and Canadian hosting is available, chosen at implementation. Our page on Canadian data residency explains the options. If you plan to keep records CRA asks you to hold in Canada in NexusCRM, raise it at implementation and confirm the setup with your accountant. You can export your full data at any time, and CRA's six-year clock is yours, not your software vendor's, so keep your own exports with your year-end records.

What it doesn't do: NexusCRM is not bookkeeping or tax software, and it does not file T4s, T5018s, WSIB reconciliations or HST returns. QuickBooks Online sync is on the roadmap, not live yet. Today, CSV exports hand the numbers to your bookkeeper or accountant. The features page has the full list.

Go into spring with everything in one place

Winter is when crews get set up. Implementation is a one-time fee and takes about two weeks for most businesses, and we do the work: your data migrated, your workflow configured, your team trained (what implementation covers). To see quotes, jobs and crew hours in one system, with receipts on each job's P&L on Pro and Elite, book a 25-minute demo or call (437) 241-6287. We'll map your lead-to-invoice flow, walk it live and give you a straight answer on fit.