--- title: "Contractor Accountant in Windsor, ON: Holdbacks, T5018, WSIB" url: https://www.everstonecpa.com/contractor-accountant-windsor description: "CPA for Windsor and Essex County contractors: 10% holdbacks, progress billing and HST, T5018 slips and WSIB clearances, fixed fee. Send an enquiry." type: service-in-a-city updated: 2026-10-02 summary: "An Ontario contractor retains and is retained a 10% holdback under the Construction Act, and bills in progress draws that carry 13% HST. It reports payments to subcontractors on T5018 slips due six months after the reporting period, and carries WSIB coverage, compulsory for most construction work." faq_count: 8 publisher: EverStone CPA Inc., a Chartered Professional Accountant firm registered with CPA British Columbia and CPA Alberta service_area: British Columbia, Alberta, Ontario and Manitoba language: en-CA contact: info@everstonecpa.com · https://www.everstonecpa.com/book-online --- [Home](https://www.everstonecpa.com/) [Accountant in Windsor](https://www.everstonecpa.com/accountant-windsor) Construction contractors General contractors & trades · Windsor # Accountant for *Windsor* contractors Windsor contractors build and refit plants, pour foundations for new subdivisions in LaSalle and Tecumseh, and renovate older houses across the city. The money arrives in stages, a tenth of it waits on the holdback, and the subcontractors all need slips. EverStone works with Essex County construction businesses remotely, as a [Windsor small business CPA](https://www.everstonecpa.com/accountant-windsor), at a fee fixed before work starts. [Get My Fixed Quote](https://www.everstonecpa.com/book-online)[Ask a Free Question](https://www.everstonecpa.com/quick-question) **Quick answer:** An Ontario contractor retains and is retained a 10% holdback under the Construction Act, and bills in progress draws that carry 13% HST. It reports payments to subcontractors on T5018 slips due six months after the reporting period, and carries WSIB coverage, compulsory for most construction work. For Windsor businesses, EverStone keeps the books, tracks holdbacks and work in progress, files HST and slips, and prepares the year-end, remotely at a fixed fee. Published fees start at $325 a month for bookkeeping and $125 for a personal return. The year-end covers the T2 with Schedule 1 and Schedule 50, the CCA schedule, the small business deduction, T4 or T5 slips for the owner’s pay, and the instalments for the year ahead. ## The 10% holdback, on both sides of the ledger Ontario’s Construction Act requires the payer on a construction contract to hold back 10% of each payment until the lien period has passed. A Windsor general contractor sits in the middle: its client holds back 10% of what it bills, and it holds back 10% of what it pays its subcontractors. Both amounts belong in the books, as holdback receivable and holdback payable, and both have to be released when the time comes. A ledger that records only the cash received shows a job as less profitable than it was and loses track of money still owed to the business. We record holdbacks by job and follow up releases, so a completed project does not leave a tenth of its value forgotten. [Construction holdback accounting](https://www.everstonecpa.com/blog/construction-holdbacks-accounting-canada) covers the entries. The Act also sets prompt payment rules: once a proper invoice is given, the owner and each contractor down the chain have set periods to pay or to give notice of non-payment. Those rules only help a contractor whose invoices are dated, addressed and supported properly, and whose books show which invoice is late on which job. We keep receivables aged by project so a late draw is visible the week it becomes late, not at year-end. ## Progress billing and work in progress Most contracts of any size are billed in draws against a schedule of values or a percentage complete. HST at 13% is generally payable on each progress billing when it is invoiced or payable, so the HST return follows the invoices rather than the cash. The holdback portion is the exception: tax on it generally becomes payable when the holdback is paid or falls due, so it is tracked separately. At year-end, a job part-finished has costs sitting against revenue that has not all been billed, or billings ahead of the work done. Those differences are recorded as work in progress or deferred revenue so the year’s profit reflects the work actually performed. We set a consistent method by job, which also shows which jobs are over or under their estimate while there is still time to act. ## T5018 slips for subcontractor payments A business whose main activity is construction reports payments to subcontractors for construction services on T5018 slips and a summary. They are due six months after the end of the reporting period, which can be the calendar year or the fiscal year, chosen once and kept. The slip needs each subcontractor’s legal name, address and business number, which is much easier to collect before the first cheque than after the last. We tag subcontractor payments in the books as they are made, so the slips come straight from the ledger. The [T5018 tracker](https://www.everstonecpa.com/t5018-subcontractor-tracker) helps collect the details, and [T5018 reporting](https://www.everstonecpa.com/blog/t5018-subcontractor-reporting-construction) explains who must file. ## WSIB and clearance certificates WSIB coverage is compulsory for most construction work in Ontario, and it is separate from the CRA with its own registration, rate groups and premium reporting. Before paying a subcontractor, a Windsor contractor should hold a current clearance certificate showing the subcontractor’s WSIB account is in good standing; without one, the contractor can be held liable for the subcontractor’s unpaid premiums. Independent operators and executive officers have their own rules on whether they need coverage. We reconcile WSIB insurable earnings to payroll each period and keep a clearance record for every subcontractor on file, so the question has an answer when a general contractor or an auditor asks. ## Subcontractor or employee Construction relies on subcontractors, and the CRA looks closely at whether someone called a subcontractor is really an employee. A worker who uses the contractor’s tools, works the contractor’s hours under its direction and cannot make or lose money on the job is usually an employee, whatever the invoice says. A wrong call means CPP, EI and income tax that should have been withheld, assessed on the contractor. We review how your crews are engaged and set up payroll for those who are employees. [Subcontractor or employee](https://www.everstonecpa.com/blog/subcontractor-vs-employee-cra) sets out the test. ## Trucks, equipment and the winter slowdown Pickups, dump trucks, excavators, skid steers and trailers are deducted through capital cost allowance by class, with the half-year rule generally halving the first-year claim and recapture arising when a unit is traded for more than its remaining cost. Vehicles used partly for personal driving need a log; [vehicle deductions](https://www.everstonecpa.com/blog/vehicle-mileage-deductions-canada-business) explains what it has to show. Essex County has milder winters than much of Ontario, but outdoor work still slows when the ground freezes, and a year’s cash is often made from spring to fall. Monthly books with holdbacks and receivables aged by job show whether the winter is covered. [Managing cash in a seasonal business](https://www.everstonecpa.com/blog/managing-cash-flow-seasonal-business-canada) goes further. ## Crews, payroll and what it costs Construction payroll brings source deductions to the CRA, Ontario Employer Health Tax once payroll passes the exemption, WSIB premiums and records of employment each time a crew is laid off. The typical trades-corporation bundle of bookkeeping, payroll and a year-end T2 with statements is usually $500 to $700 a month, fixed in writing after we review your enquiry. Monthly bookkeeping on its own starts at $325 a month with HST filing included. [Payroll services in Windsor](https://www.everstonecpa.com/payroll-services-windsor) and [Windsor bookkeeping](https://www.everstonecpa.com/bookkeeping-windsor) describe the recurring work, and the [pricing page](https://www.everstonecpa.com/pricing) lists every fee. About this article **EverStone CPA** Prepared and reviewed by a Chartered Professional Accountant at EverStone CPA, a CPA firm working with small and midsized businesses in BC, Alberta, Ontario and Manitoba. Updated September 2026 . [About the firm](https://www.everstonecpa.com/about) · [Send an enquiry](https://www.everstonecpa.com/book-online) ## What a Windsor contractor has to track What a Windsor contractor has to track The items that decide a construction year-end — for a business operating in Windsor, Ontario | Item | Why it matters | | Holdbacks | 10% retained under the Construction Act, receivable and payable | | Progress billings | HST due as invoiced; work in progress at year-end | | Subcontractor payments | T5018 slips six months after the reporting period | | WSIB | Compulsory for most construction; clearance certificates | | Sales tax where you operate | 13% HST, a single registration and a single return | Source: [Construction and trades accounting](https://www.everstonecpa.com/construction-trades-accounting). General information, not advice. For the national picture, see [accounting for contractors in BC, Alberta, Ontario and Manitoba](https://www.everstonecpa.com/contractor-accountant). Common questions ## Windsor contractor accounting FAQ **When is HST due on the holdback portion?** Generally when the holdback is paid or becomes due, not when the progress billing goes out. The rest of the billing is reported when invoiced or payable, so the holdback has to be tracked separately in the books. [Ask about your case →](https://www.everstonecpa.com/quick-question) **Do I have to file T5018 slips?** If construction is your main business and you pay subcontractors for construction services, yes. Slips are due six months after your reporting period ends. **What if a subcontractor has no WSIB clearance?** You can be held responsible for their unpaid premiums on your job. Get a clearance certificate before paying and renew it as the job runs. **Should my contracting business incorporate?** Often, once profit is more than you need to draw each year, because retained profit is taxed at a lower corporate rate. Liability, bonding and lender requirements also play a part. We compare the options on your actual numbers. **My books are a year behind. Can you catch them up?** Yes. We rebuild the missing months from bank records and invoices, set up holdback and job tracking as we go, and then move you onto monthly bookkeeping. **Do you work with renovators and small trades?** Yes, from sole proprietors to incorporated general contractors across Windsor, LaSalle, Tecumseh, Lakeshore and the rest of Essex County. **What does an accountant cost for a Windsor construction business?** Windsor businesses pay the same published fees as everyone else. Monthly bookkeeping starts from $325 a month and a personal return from $125; a corporate return is quoted after we review your enquiry. A single question can go to a 45-minute Advice Call, a flat fee of $225 + GST. Every fee is fixed in writing first. [See the published fees](https://www.everstonecpa.com/pricing). **Do you work with businesses outside Windsor itself?** Yes. Contractors in LaSalle, Tecumseh, Lakeshore, Leamington and the rest of Essex County are served the same way as those in Windsor, remotely and at the same fixed fees. ## Related services and local guides Nearby cities, the rest of what we do for Windsor businesses, and the reference pages behind this one. [Accountant for Windsor manufacturers Job costing and work in progress for tool, die and mould shops.](https://www.everstonecpa.com/manufacturer-accountant-windsor) [Corporate tax accountant in Windsor The T2 and year-end planning for incorporated contractors.](https://www.everstonecpa.com/corporate-tax-accountant-windsor) [Contractor accountant in London, Ontario The same construction engagement, serving London.](https://www.everstonecpa.com/contractor-accountant-london-ontario) [Contractors in Hamilton The same construction engagement, serving Hamilton](https://www.everstonecpa.com/contractor-accountant-hamilton) [Personal tax (T1) in Windsor Returns for sole-proprietor trades](https://www.everstonecpa.com/personal-tax-accountant-windsor) [Greenhouses in Essex County Accounting for the growers many local contractors build for](https://www.everstonecpa.com/greenhouse-accountant-windsor) [Form T5018 The construction subcontractor slip explained](https://www.everstonecpa.com/forms/t5018) [Accountants across Ontario Remote CPA service throughout Ontario](https://www.everstonecpa.com/accountant-ontario) [Ontario tax facts Current rates and thresholds for Ontario](https://www.everstonecpa.com/ontario-tax-facts) ### What clients say Rated 5.0 on Google across 21 client reviews. [Read all reviews](https://www.everstonecpa.com/reviews) ★★★★★ “…have been completing my bookkeeping, taxes and financials for the last 2 years and they have been amazing. Thank you!” R. H. Verified Google review ★★★★★ “…We switched to him last year for both our personal and small-business taxes — responsive, knowledgeable and quick.” Heather Powers Verified Google review ### Starting fees Every fee is fixed in writing before any work begins. - **Monthly bookkeeping, GST/PST filing included** from $325 a month - **Payroll, remittances, T4s and ROEs** included in monthly bookkeeping - **Books, payroll and the year-end T2 together** $500–$700 a month - **Corporate year-end and T2 return** fixed fee, quoted in writing - **Personal tax return (T1)** from $125; self-employed or rental $275–$500 - **Catch-up bookkeeping** from $2,200 per year of records - **Controller or CFO support** controller from $1,650, CFO from $2,750 a month - **One-off advice call with a CPA** $225 plus GST [Get My Fixed Quote](https://www.everstonecpa.com/book-online?service=monthly#enquiry-form) ## Contracting in Windsor or Essex County? One CPA for holdbacks, progress billing, T5018 slips, WSIB and the year-end. Fixed fee, fully online. Send an enquiry. [Get My Fixed Quote](https://www.everstonecpa.com/book-online)[Ask a Free Question](https://www.everstonecpa.com/quick-question) ## Remote accounting for contractors EverStone is a one-CPA firm that works online. serving Windsor contractors remotely. **There is no Windsor office and no local staff.** Invoices, draws and subcontractor details come in through a secure upload link, calls happen after the site closes if that suits, and nobody has to leave a job to meet an accountant. ## Talk to a CPA about this One Chartered Professional Accountant, start to finish. Fixed fees, quoted in writing before any work begins, and no obligation from a first conversation. [Get My Fixed Quote](https://www.everstonecpa.com/book-online) [Ask a Free Question](https://www.everstonecpa.com/quick-question) Email info@everstonecpa.com --- Source: https://www.everstonecpa.com/contractor-accountant-windsor Prices: https://www.everstonecpa.com/pricing · Contact: info@everstonecpa.com · https://www.everstonecpa.com/book-online