How to switch payroll providers in Ireland
Reviewed by Mellow Editorial Team, HR & payroll content team
Switching payroll providers in Ireland is straightforward if you follow the right sequence. The main risk is not the switch itself — it is carrying over incorrect year-to-date figures, which can cause tax miscalculations for the rest of the year.
Understand what you are actually moving
Payroll is not just a list of names and salaries. When you switch mid-year, you are moving:
- Year-to-date gross pay, tax, USC and PRSI figures for every employee
- Tax credit certificates (P2Cs) issued by Revenue for each employee
- Any outstanding sick pay, parental leave or benefit-in-kind records
- Your Revenue Employer Registration details and ROS credentials
If you are switching at the start of a new tax year — 1 January — the process is cleaner because cumulative figures reset to zero. Mid-year switches are entirely workable but require more careful data handover.
Get your data out of your current provider
Before you give notice to your existing provider, export everything. You want:
- A full payroll history for the current tax year (2026/27), broken down by employee and pay period
- Year-to-date totals for gross pay, income tax deducted, USC deducted, employee PRSI (Class A: approximately 4.1% of reckonable earnings) and employer PRSI (approximately 11.15%)
- A copy of each employee's current tax credit certificate from Revenue
- Details of any deductions — pensions, attachment of earnings orders, salary sacrifice arrangements
Ask for these in a structured format, ideally a spreadsheet. Most providers will supply this as part of their standard off-boarding. If yours does not, request it formally in writing.
Do not cancel your access to the old system until you have confirmed the new system has imported everything correctly.
Set up your new provider correctly
Your new provider needs to be authorised to file on your behalf through ROS (Revenue Online Service). Under Ireland's real-time reporting rules, a payroll submission — the Payroll Submission Request, or PSR — must be made to Revenue on or before each payday. There is no grace period. If your new provider is not set up in time for your next pay run, you could miss a filing deadline.
The practical steps here are:
1. Add your new provider as an agent on your ROS account, or confirm they are already registered as a payroll bureau with Revenue.
2. Provide them with your Employer Registration Number (ERN).
3. Upload or re-enter the year-to-date figures from your data export. Your new provider should validate these against the figures Revenue holds before the first live pay run.
4. Import current tax credit certificates for all employees. Revenue issues these electronically; your new provider can retrieve them via ROS once they have agent access.
Build in enough lead time — a minimum of two to three weeks before your next payday is a reasonable working assumption, more if you have a large or complex workforce.
Run a parallel pay calculation before going live
Before your first live payroll on the new system, ask your new provider to run a parallel calculation on the most recent pay period using the old system's data. Compare the outputs line by line. Pay particular attention to:
- Cumulative income tax: at the 20% standard rate up to the relevant annual threshold, and 40% above it
- USC banding — the 0.5%, 2%, 3% and 8% bands need to apply correctly to cumulative figures, not just the current period's pay
- PRSI class applied to each employee
- Any employees on week-one or emergency basis — these are easy to miss in a migration
Discrepancies at this stage are far easier to fix than after you have already paid your employees and filed with Revenue.
Notify your employees and update pension records
Employees do not need to do anything when you switch providers, but it is good practice to let them know their payslips may look slightly different — different formatting, a new portal login, or a revised payslip layout. Reassure them that their tax credits and cumulative figures carry across.
If your business is enrolled in a pension scheme, or if you are preparing for the introduction of My Future Fund auto-enrolment from 2026, update your pension provider with the new payroll contact details and confirm how contribution data will be transmitted each period. Contribution records need to stay in sync with payroll, so this handover is worth treating as a separate checklist item rather than an afterthought.
Once your first pay run on the new system files successfully with Revenue and employees receive correct payslips, the migration is complete. Keep your exported data from the old system on file for at least six years in line with standard Revenue record-keeping requirements.
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