Construction accountancy in Northern Ireland

Construction is the most paperwork-heavy industry on the books. CIS deductions, VAT reverse charge, retentions, applications for payment, and a workforce that flexes by the project. We work with NI builders, contractors, and subcontractors who need their accountant to know the difference between an application and an invoice.

Talk to us about construction

Construction accountancy lives or dies on cash flow. Retentions sit on the balance sheet for months. Applications for payment turn into invoices turn into receipts on someone else's timetable. CIS deductions come off subcontractor payments and need monthly returns. The VAT domestic reverse charge changes who accounts for VAT on most building work.

We work with main contractors, subcontractors, mechanical and electrical specialists, joiners, plumbers, groundworkers, and developers across Northern Ireland. From sole-trader trades to limited-company contractors with twenty on the books, the financial dynamics rhyme: a project-by-project P&L, retentions tying up cash, and VAT and CIS rules that punish the unwary.

Our construction clients tell us two things matter: clean monthly CIS and reverse-charge handling, and an accountant who can show them which projects actually made money once costs were fully loaded.

What construction businesses ask us

01

CIS deductions and returns

Verifying subcontractors with HMRC, calculating gross or 20% / 30% deductions correctly, filing CIS returns monthly, and reconciling against subcontractor statements.

02

VAT domestic reverse charge

Knowing when reverse charge applies, getting the invoice wording right, and handling the cash-flow knock when output VAT disappears off the till.

03

Retentions and WIP

Retentions held by the client are an asset on your books. Application-for-payment work in progress sits alongside it. Getting both right at year end matters for tax and for your funder.

04

Project-level profitability

Job costing that compares contract value to actual cost. Spotting margin slip early. Producing a project P&L that informs the next quote.

05

Capital allowances on plant

Annual Investment Allowance on tools, plant, and vehicles. Full expensing on qualifying assets. Getting the timing right around accounting periods.

Frequently asked about construction accountancy

Do you handle CIS for contractors and subcontractors?

Yes. We verify subcontractors, calculate deductions, file monthly CIS returns, issue subcontractor statements, and reconcile CIS suffered for limited-company subcontractors against PAYE. It is part of our standard payroll service for construction clients.

How does the VAT domestic reverse charge work?

For most building and construction services supplied between VAT-registered businesses, the customer accounts for the VAT, not the supplier. The supplier issues a reverse-charge invoice with no output VAT shown. We make sure your invoicing, your software, and your VAT return all line up correctly.

Can you produce project-by-project P&L?

Yes. We configure Xero or Sage with tracking categories per project so you can see contract value, cost to date, and margin in real time. The reports inform pricing on the next tender and protect you from a project running away on cost.

I am a sole-trader contractor. Does MTD for Income Tax affect me?

If your gross self-employment income is over £50,000, yes, from April 2026. Over £30,000, from April 2027. Over £20,000, from April 2028. We handle MTD setup, software, and quarterly updates as part of the service.

Talk to an accountant who understands construction in NI

15-minute call. No commitment. We will answer your questions and outline how we work with construction businesses across Northern Ireland.

028 9508 4138