An employer's tax and HR calendar for the United Kingdom
Reviewed by Mellow Editorial Team, HR & payroll content team
The UK employer calendar runs on fixed HMRC deadlines and statutory dates that repeat every tax year (6 April to 5 April). Miss one and you risk penalties, interest or employment tribunal claims — so mapping them out in advance is the most practical thing you can do.
April — the tax year begins
6 April marks the start of the new tax year. On this date, update your payroll software with any new tax codes HMRC has issued, apply the current National Insurance thresholds and rates (employer NI is 13.8% on earnings above the secondary threshold; employee NI is 8% up to the upper earnings limit, then 2% above it), and confirm your auto-enrolment pension contribution minimums are correct (employer 3%, employee 5% of qualifying earnings).
If you have new starters joining from 6 April, check whether the Employment Rights Act 2025 changes affect any contracts or policies — it strengthened day-one rights, so your standard employment terms may need reviewing.
May — issue P60s
Every employee on your payroll on 5 April must receive a P60 by 31 May. This summarises their total pay and deductions for the year just ended (2025/26 in the previous cycle; 2026/27 in the current one). You cannot issue a P60 to someone who left before 5 April — they should have received a P45 when they left.
Practically: run your end-of-year payroll finalisation before this deadline. Most payroll software generates P60s automatically once you've submitted your final Full Payment Submission (FPS) for the year.
June — ongoing RTI and mid-year checks
There is no single June deadline, but Real Time Information (RTI) runs continuously. You must submit a Full Payment Submission to HMRC on or before every payday, without exception. If you pay weekly, that's 52 FPS submissions a year. If you pay monthly, it's 12. Late or missing FPS submissions attract automatic penalties.
June is also a sensible point to audit your payroll data — check for new starters who haven't been added correctly, leavers whose records haven't been closed, and any employees who should have been auto-enrolled into a pension scheme. The auto-enrolment trigger and postponement rules mean it's easy for borderline cases to slip through.
July — P11Ds and expenses reporting
6 July is the deadline for submitting P11D forms to HMRC and providing copies to the relevant employees. P11Ds report benefits in kind — company cars, private medical insurance, loans, and other non-cash benefits provided during the tax year ending 5 April.
If you've registered for payrolling benefits (reporting them through payroll in real time rather than on a P11D), you don't need to submit P11Ds for those specific benefits, but you still need to submit a P11D(b) to declare the Class 1A National Insurance due. That Class 1A NI payment is also due by 19 July (22 July if paying electronically).
Throughout the year — leave, sick pay and statutory payments
Statutory annual leave entitlement is 5.6 weeks (28 days including bank holidays for a full-time, five-day-week employee). Workers accrue leave from day one of employment, and under the strengthened day-one rights introduced by the Employment Rights Act 2025, entitlements and protections apply earlier than they did previously.
Statutory Sick Pay applies when an eligible employee is off sick; statutory family-leave payments (maternity, paternity, shared parental, adoption) apply at various rates and for varying durations depending on the type of leave. You are responsible for paying these through payroll and recovering most or all of the cost from HMRC via your regular payroll process. Keep records of all qualifying periods carefully — HMRC can request evidence during compliance checks.
A condensed reference
| Date | What to do |
|---|---|
| 6 April | Apply new tax year rates, codes and thresholds |
| 31 May | Issue P60s to all employees in post on 5 April |
| Every payday | Submit FPS via RTI on or before payment date |
| 6 July | Submit P11Ds (benefits in kind) to HMRC and employees |
| 19/22 July | Pay Class 1A National Insurance on benefits |
| Year-round | Auto-enrolment assessment, SSP, statutory family leave |
One area that catches employers out is the interaction between RTI deadlines and irregular pay runs — for instance, paying a bonus outside your normal cycle. That bonus still requires an FPS on or before the date it is paid. If you're managing payroll across more than one entity or jurisdiction, tools that centralise RTI submissions can reduce the risk of a missed filing, as described in how Mellow runs payroll across six countries.
The calendar does not get simpler as your headcount grows — if anything, the volume of RTI submissions, benefit-in-kind calculations and leave calculations increases. Knowing the fixed points in the year lets you resource them properly rather than treating them as surprises.
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