Your CIS, VAT and tax work exactly the same here as anywhere in the UK. Six things do not, and the first of them applies the day you take a job in the Republic.
Cross the border and you are not in CIS at all. Irish Relevant Contracts Tax takes 0%, 20% or 35% — and 35% if Revenue have never heard of you.
What to sort out firstCITB NI is a separate board with its own threshold of £80,000. The Great Britain exemption is £150,000, so the same firm pays here and not there.
Work out if you payPayroll is UK-wide and unchanged. The law around it is not: the three-step dismissal procedure is still compulsory here, and monitoring duties start at eleven employees.
Before you hireThe levy that starts in October 2026 comes from an England statutory instrument, and so do the dutyholder and competence duties. Neither reaches a site here.
What the levy actually isThe Building Regulations (Northern Ireland) 2012, run by the eleven district councils, with two days’ written notice before certain operations start.
The Northern Ireland positionA regional rate plus your council’s district rate, on a value set by Land & Property Services. No English multiplier, no Valuation Office.
What it costs
Irish Revenue run their own withholding scheme for construction, and it applies to you from the first payment.
One thing worth saying plainly: the Windsor Framework is about goods. If you fit kitchens in Antrim you are selling a service and none of it reaches you. Anyone telling you that you need an XI EORI number has you confused with an importer.
Your bill is a regional rate plus your council’s district rate, applied to a net annual value that Land & Property Services sets rather than the Valuation Office Agency. For the year ending 31 March 2027 the regional rate on business property is 30.79p in the pound. The district rate is set separately by each of the eleven councils, which is why the same unit costs different money in Fermanagh and in Derry.
Small Business Rate Relief is applied automatically, so there is nothing to claim — but a small yard often sits inside the bands:
Our business rates calculator covers England, Scotland and Wales only. A multiplier-based calculator would give you a confidently wrong answer here, so look your value up with Land & Property Services and add your district rate — or ask us and we will do it with you.
Northern Ireland is our largest base.
Most people do the whole thing by phone, video and WhatsApp, because that suits a working day on site. But if you would rather come in and go through it across a desk, you can.
Arrange a time ↗In person, by phone or by video — whichever is easier. There is no charge for the first conversation.
No. CIS is a UK-wide scheme run by HMRC and it works here exactly as it does in England — 20% standard, 30% for an unverified subcontractor, the return by the 19th and the payment by the 22nd. The anti-fraud rules starting on 6 April 2026 apply in full. What you meet on a site in the Republic is a different scheme altogether, called Relevant Contracts Tax.
Because 35% is the rate Irish Revenue apply to a subcontractor with a poor compliance record, or to one who has not registered with them at all. For a Northern Irish trade on a first job south of the border it is almost always the second. You are not in trouble; you are simply unknown to them. Registering for Irish tax and getting a rate determined is what moves you off it, and it is far better done before the job than after.
No. It comes from The Building Safety Levy (England) Regulations 2025, which as the title says is an England instrument, and it starts on 1 October 2026 in England only. The dutyholder and competence duties are England-only too. Building control here runs under The Building Regulations (Northern Ireland) 2012, administered by the district councils. If somebody has quoted you for levy liability on a scheme here, check which nation the instrument names before you budget for it.
Almost certainly not. XI numbers belong to the rules for moving physical goods in and out of Northern Ireland. A trade business selling labour and installed materials on sites here is supplying a service, and services follow UK rules. It can start to matter if you are buying materials in quantity from the Republic or the EU, or selling product rather than fitting it — and that is worth a specific conversation rather than a rule of thumb.
Yes, at Unit 13:62 Fenaghy Road, Ballymena, Co. Antrim, BT42 1FL, and Northern Ireland is our largest base. You can meet somebody there by appointment. Most of the work still runs by phone, video and WhatsApp because that is what suits people who are on site all day, and nothing about your tax position depends on being able to drive to us.
No. Sole traders start at £29 + VAT a month and limited companies at £49 + VAT a month, the same as everywhere else we work. Payroll and CIS support are priced separately. If your work crosses into the Republic there is more to do, and we will say so before you sign anything rather than quoting you a low number and revisiting it.
Tell us where your work is and we’ll talk through the next steps.
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Get my quote ↗Accounts, tax and business support. All agreed upfront.