Best payroll software for accountants UK: client management

What to take away

• Multi-client payroll software earns its place when it shortens weekly admin across many small clients, not when it adds the longest feature list.
• Agent authorisation, PAYE scheme linking and RTI filing for each client sit at the centre of the buying decision in UK practices.
• Test pension duties, payslip content and employee data handling before you sign, because those duties fall on your client and on your firm.
• Price the whole book, including per-scheme fees, parallel runs and the hours your team spends on corrections and queries.

Where client payroll software differs from a single-employer tool

A payroll tool built for one employer assumes one PAYE scheme, one pay date and one set of pension rules. A practice runs many of each. The software must hold client records apart, switch between them quickly and leave a clear audit trail. That is the first test a shortlist should pass.

Ask how the product separates client data. A shared log-in with a client selector is common and workable. What matters is whether a mistake in one client's run can reach another client's figures, and whether the audit log names the person who changed it.

Getting agent authorisation and RTI filing right

1. Apply for an agent services account so the practice can act for clients online.
2. Have each client authorise you through their own Government Gateway credentials.
3. Link every PAYE scheme to the practice account before you file for that client.
4. Connect the software to HMRC and run a test submission ahead of the first live pay date.
5. Record who holds each authority, and remove it the day a client leaves.

Authorities move with the client. When a client appoints another accountant, the old authorisation has to go, and the software should make that removal easy to record. Keep a simple register of schemes, authorities and filing deadlines so nothing relies on one person's memory.

Multi-client features worth testing

Run the same tests on every product you demo, using two real client scenarios rather than a vendor's sample data.

What to test	Why it matters in a practice
Client switching	Deadlines for several small employers often land on the same day.
Bulk RTI filing	One rejected scheme must be visible on its own, not lost in a batch.
Pension data	Assessment, postponement and re-enrolment run per client, with a contribution file per provider.
Corrections	Amended FPS submissions need a trail so you can explain what changed.
Access control	Partners, managers and juniors should not all see every client's pay data.
Time and cost reporting	The firm cannot price the work without per-client hours.

If construction clients are on the books, CIS deductions and subcontractor verification need testing before you commit; our notes on payroll software for CIS subcontractors set out what to check.

Data, pensions and payslips

A practice usually acts as a data processor for the client's employee data, while the client stays the controller. The ICO's UK GDPR guidance explains what that split requires, including a written contract and limits on using the data for anything else.

Auto-enrolment duties belong to the client employer under the Pensions Act 2008, so the software must handle assessment, postponement and re-enrolment per client, then produce the contribution file the provider expects.

Workers have a right to an itemised pay statement under the Employment Rights Act 1996. Check that each client's payslip format is supported, and that copies stay retrievable for as long as the engagement requires.

Pricing a practice-wide licence

Vendors price practice licences in different ways: per PAYE scheme, per employee across the whole book, or as a platform fee plus a charge for each run. Ask for a quote using your actual client count and employee bands, not a headline figure.

Migration is where practices lose time. Moving a whole client book between systems is a project in itself, and our guide to switching payroll software covers the sequence that protects pay dates.

Before you sign, list the tasks you will still do by hand: chasing client approvals, checking starter and leaver data, and reconciling pension files. If that list is long, the licence fee is not the real cost.

Common questions

Can one payroll product file RTI for several PAYE schemes?

Yes. A practice files for many schemes through an agent services account, with each client linked separately. Check how the software reports failures per scheme, because a rejected submission should not be buried inside a batch.

Do accountants need different payroll software from their clients?

Often, yes. A product built for one employer rarely handles client switching, bulk filing or partner-level access. Some practices run a bureau-grade tool for managed clients and keep a simpler system for employers who file themselves.

How should a practice price payroll work?

Build the fee from the time the run actually takes, including queries, corrections and pension files. Software charges and per-scheme fees belong in that calculation rather than in a separate line.

Is multi-client payroll software worth it for a small practice?

Test it against the hours you spend on manual client admin. On a modest book of small employers the time saved on filing and corrections usually decides the case, but run the numbers on your own client list before committing.