Payroll penalties are among the most aggressive in the UK tax system because they are almost entirely automatic, no human review, no warning letter, and the charge often arrives before you know the filing was late. This guide explains how Real Time Information (RTI) penalties, PAYE late-payment surcharges and interest interact, the grounds on which HMRC will entertain an appeal, and the operational changes that stop repeat failures.
Late Filing Penalties (the FPS)
HMRC charges a monthly penalty when an FPS is filed after the on-or-before-payday deadline. The amount scales by headcount on that submission:
| Employees on the FPS | Monthly Late-Filing Penalty |
|---|---|
| 1 - 9 | £100 |
| 10 - 49 | £200 |
| 50 - 249 | £300 |
| 250+ | £400 |
The First-Default Concession
HMRC does not charge a penalty on the first late FPS in any tax year. From the second late submission onwards, each triggers the full monthly penalty. This concession is per PAYE scheme, not per employer group, a single slip mid-year quietly burns the shield, so the next late filing (however accidental) costs money.
Additional 5% penalty applies where an FPS is more than 3 months late. This is applied to the tax and NI the filing should have reported, not to the monthly penalty. Large employers running payroll for 250+ staff can therefore see five-figure exposure on a single overdue submission.
Late Payment of PAYE
Separately from filing, PAYE and NI must reach HMRC by the 22nd of the following tax month (electronic) or the 19th (cheque). Late payment attracts a percentage surcharge on top of interest:
| Number of late payments in the year | Surcharge on the late amount |
|---|---|
| 1 | No surcharge (first default free) |
| 2 - 4 | 1% |
| 5 - 7 | 2% |
| 8 - 10 | 3% |
| 11 or more | 4% |
Interest is charged on top of the surcharge, at HMRC's official rate (Bank of England base + 4%, 8.25% at the time of writing). The clock starts the day after the due date and runs until the payment clears in HMRC's account. BACS typically takes 3 working days; Faster Payments and CHAPS clear same-day. Paying on the 22nd by BACS therefore arrives late, a common avoidable mistake.
Payments of £30,000 or more in a single month can be made by Direct Debit under HMRC's "Variable Direct Debit" scheme, which removes the manual scheduling error entirely. We recommend this for any employer whose PAYE liability has crossed £30k more than twice in the last year.
Auto-Enrolment Penalties (The Pensions Regulator)
The Pensions Regulator (TPR) enforces auto-enrolment compliance independently of HMRC. The enforcement sequence is:
- Compliance Notice, a formal instruction to take specific action within a stated deadline. No financial penalty at this stage.
- Fixed Penalty Notice, £400 issued when the compliance notice is ignored.
- Escalating Penalty Notice, daily fines that scale with workforce size: £50/day for 1-4 staff, £500/day for 5-49, £2,500/day for 50-249, up to £10,000/day for 500+ staff.
- Criminal prosecution, reserved for wilful failure or for inducing employees to opt out.
TPR publishes enforcement outcomes quarterly. Small employers who ignore the first letter genuinely do accumulate multi-thousand-pound daily fines, the regulator does not bluff.
Appealing a Penalty
An RTI or PAYE penalty can be appealed within 30 days of the notice. HMRC's appeal forms sit inside your PAYE Online account or can be submitted in writing. The grounds that succeed are narrow:
- -Reasonable excuse, serious illness, bereavement, fire, flood, theft of records, HMRC system failure, postal delay beyond your control. The excuse must be unexpected and must directly have caused the delay, and you must have filed or paid as soon as it ended.
- -Special circumstances, exceptional, uncommon circumstances that make the penalty disproportionate. Rare; usually a back-stop when reasonable excuse narrowly fails.
- -Factual error, the filing was on time but HMRC recorded it incorrectly, or the employee count used to set the penalty tier is wrong.
Software issues are not normally a reasonable excuse. HMRC's position is that you are responsible for choosing a reliable provider. An exception exists where the provider has issued a written confirmation that the fault was at their end, in which case HMRC will usually accept the appeal. This is one reason BrightPay, Xero and Sage maintain public status pages, the archived incident report becomes the evidence.
What Doesn't Count as a Reasonable Excuse
- Cashflow shortages ("couldn't afford to pay").
- Finding the rules confusing.
- Forgetting the deadline.
- A third party (accountant, bookkeeper) let you down, unless you took reasonable care in appointing and supervising them.
How to avoid repeat penalties
- 1.Lock payday to the same date every month. A consistent date makes the FPS deadline predictable and removes the ambiguity HMRC catches employers on (paying "last Friday of the month" means the deadline moves).
- 2.File the FPS the day before payday. HMRC explicitly permits this ("on or before"). It removes the same-day rush and means a BACS or system outage on payday doesn't cause the filing to slip.
- 3.Pay PAYE by Faster Payments or Direct Debit. BACS takes 3 working days and is the single most common cause of accidental late payment. FPS software integrations with HMRC allow Direct Debit setup directly from the payroll file.
- 4.Set an annual scheme if you're director-only. Reduces twelve FPS submissions to one. See our director-only payroll guide.