Working for a UK employer from Dublin: Irish tax, PRSI and posting certificates
The Common Travel Area lets you work in Ireland without a permit, but it doesn't stop Revenue taxing the salary you earn at your kitchen table in Drumcondra.
The short version
- Irish PAYE follows the work, not the payslip. Pay for duties performed in Ireland is within Irish PAYE, whether your employer is Irish or British [1].
- Your UK employer may have to register as an employer in Ireland and run Irish payroll, deducting Income Tax, USC and PRSI [1][2].
- PRSI (Ireland's National Insurance) usually applies if you live and work in Dublin. The exception is a genuine posting of up to 24 months under the UK–Ireland social security convention, proved with a certificate of coverage from HMRC [3][4].
- Short trips are different. Revenue's rules relieve employers from Irish PAYE for business visitors with 30 or fewer Irish workdays a year, and in some cases up to 60 [1].
- The UK side needs sorting too: a P85, the right UK tax code, and a log of any UK workdays. A tax adviser who knows both countries can check your case.
Two questions: tax and social security
People tend to lump these together, but they follow different rules.
| Question | What decides it | Who issues the paperwork |
|---|---|---|
| Who taxes my salary? | Where you're tax resident, where you do the work, and the UK–Ireland double taxation agreement | Revenue and HMRC |
| Where do I pay social insurance? | The UK–Ireland Convention on Social Security | HMRC (for UK cover) or Revenue and the Department of Social Protection (for PRSI) |
It's perfectly possible to pay Irish income tax and UK National Insurance at the same time. That's the normal result of a short posting with a certificate.
Irish income tax: when Revenue wants its share
If you move to Dublin and work from here
Once you live in Ireland you'll usually be Irish tax resident: 183 days or more in the tax year does it, and there's also a two-year test of 280 days [1]. Irish residents are taxed on their worldwide income, with relief under the double taxation agreement for any tax paid elsewhere [1][5].
Revenue's Tax and Duty Manual on non-Irish employments (reviewed May 2026) is clear: pay for work performed in Ireland comes within Irish PAYE, whatever the residence of the employee or the employer [1]. If you work wholly from Dublin, all your pay is in. If you split your time, only the share for Irish workdays is [1].
That puts the duty on the employer. A UK company with staff working in Ireland has to register as an employer with Revenue, report each payment in real time and deduct Income Tax, USC and PRSI [1][2]. Non-resident companies register on form TR2 (FT), and non-resident individuals on TR1 (FT) [2]. Revenue's rules also let it look to an intermediary or the Irish business where you work if the foreign employer doesn't operate PAYE [1].
In practice, many UK employers either register in Ireland and run an Irish payroll (often called a shadow payroll), or use a local payroll provider or employer-of-record service. Some will say no to the move altogether. Raise it with HR in writing before you sign a lease.
Whatever the payroll arrangement, the income is still taxable in Ireland. If it isn't taxed through Irish PAYE, it has to be declared to Revenue another way, so don't assume a UK payslip means nothing is due here.
Split working patterns
If you'll work partly in Dublin and partly in the UK, Revenue's manual says only the Irish share is subject to Irish PAYE. Where that share can't be worked out in advance, the employer can ask Revenue for a direction under section 985E [1]. Keep a diary of where you work each day; both tax offices may ask.
Short-term visits to Ireland
If you still live in the UK and just come over for meetings, Revenue relaxes the rules for employers in a treaty country such as the UK [1]:
| Irish workdays in the tax year | Irish PAYE for a UK employer? |
|---|---|
| Up to 30 | No PAYE obligation |
| 31 to 60 | No PAYE if the treaty's short-stay conditions are met |
| 61 to 183 | PAYE applies unless Revenue has given a dispensation |
| Over 183 | PAYE applies |
A dispensation has to be applied for in writing within 30 days of the work starting, and each tax year is looked at separately [1]. This table is for business visitors. It doesn't fit someone who has actually moved to Dublin.
PRSI and the UK–Ireland social security convention
The UK and Ireland signed a Convention on Social Security in Dublin on 1 February 2019, which took effect at the end of the Brexit transition period [3]. The Irish government says it keeps the arrangements that existed before Brexit [6].
The general rule
You pay social insurance where you work [3]. So a Brit who lives and works in Dublin normally pays Irish PRSI, not UK National Insurance. Class A PRSI, which most employees pay, rose from 4.2% to 4.35% on 1 October 2026, and your employer pays its own share on top [7]. PRSI builds your entitlement to the Irish State Pension and other benefits, and the convention lets UK and Irish contributions count together [6].
Postings of up to 24 months
If your UK employer sends you to work in Ireland for a limited time, you can stay in UK National Insurance for up to 24 months, as long as you're not being sent to replace another posted worker [3]. Self-employed people who go to Ireland temporarily for similar work get the same 24-month rule [3].
The proof is a certificate of coverage from HMRC. Your employer first confirms with HMRC on form CA3821 that it can send staff abroad, then applies on form CA3822, which covers temporary work in EU countries, Ireland included. You can't apply more than 12 months in advance [4]. Self-employed people use CA3837, and people working in two or more countries use CA8421 [4].
A posting is a temporary arrangement. If you've moved to Dublin for good and your employer has simply agreed to let you work remotely, you're not a posted worker, and Irish PRSI is the norm.
Working in both countries
If you normally work in both the UK and Ireland, you pay into the system where you live, as long as you do a substantial part of your work there [3]. So a Dubliner who spends one week a month in the London office would usually pay Irish PRSI on the whole salary, and the UK employer would owe Irish employer PRSI. If you don't do a substantial part of your work where you live, the employer's location decides [3]. The convention doesn't put a number on "substantial", so ask HMRC or Revenue for a ruling rather than guessing.
What your UK employer needs to do
- Agree the move in writing, with where you'll live, where you'll work and for how long.
- Decide which social security system applies. For a genuine posting, apply for a certificate of coverage on CA3822 [4]. Otherwise, plan for Irish PRSI.
- Register with Revenue as an employer and set up Irish payroll, or appoint a provider to do it [2].
- Report each payment to Revenue on or before payday [1][2].
- Sort UK PAYE, so you aren't taxed in full in both countries while it's being fixed. Our guide to working abroad for a UK employer explains the UK side, including the globally mobile employee notification.
- Check the company's own position. Someone senior working from Ireland can raise corporate tax questions for the business. That's one for the employer's advisers.
What you need to do
- Get a PPS number and register for Revenue myAccount, so you're not hit with emergency tax. Our guide to your PPS number and first weeks in Ireland has the steps.
- Tell HMRC you're leaving with form P85, and check whether split-year treatment applies to the year you move. See leaving the UK and the P85.
- Keep a workday log for both countries.
- Claim double taxation relief if both countries tax the same income. The UK–Ireland double taxation agreement exists to stop that [5]. Our guide to double taxation agreements and reliefs explains how relief works.
- Think about your State Pension. If you're paying Irish PRSI, UK National Insurance stops. The convention lets the two records count together, and voluntary UK contributions may still be worth a look.
For the full picture on Irish Income Tax, USC and PRSI, see our guide to Ireland taxes for Brits. And if you want to hear how other remote workers persuaded their HR department, ask in our community group for Brits in Ireland, here.
Sources
- Revenue: Tax and Duty Manual Part 42-04-65, PAYE in relation to non-Irish employments exercised in the State (reviewed May 2026)
- Revenue: Registration of employers for PAYE (published 10 November 2025)
- GOV.UK: UK/Ireland Convention on Social Security (Treaty Series No. 6, 2021)
- GOV.UK (HMRC): Apply for a certificate confirming you will pay UK National Insurance when working temporarily abroad (CA3822) (last updated 9 May 2024)
- GOV.UK (FCDO): Living in Ireland
- gov.ie (Department of Social Protection): Social security arrangements post-Brexit
- Citizens Information: PRSI contributions increase from today (1 October 2026)