If you provide any taxable benefit to staff in the 2025-26 tax year, your P11D and P11D(b) returns are due with HMRC by 6 July 2026. Six weeks away. And the Class 1A National Insurance bill that comes with them has to clear by 22 July if you pay electronically, or 19 July by cheque.
This is also the last full P11D year for most employers. From 6 April 2027 payrolling becomes mandatory for the majority of benefits in kind, which means real-time reporting through your payroll rather than a once-a-year P11D submission. If you have not already registered to payroll benefits voluntarily for 2026-27, you cannot now do so for this current year, and you should be preparing for the mandatory regime to land. It sits on top of the wider payroll cost rise that began with the 15% employer NIC and £12.71 minimum wage from April 2026.
TL;DR: P11D and P11D(b) for 2025-26 are due 6 July 2026. Class 1A NIC is 15% (up from 13.8%), payable by 22 July electronically. Late filing costs £100 per 50 employees per month. Incorrect returns can attract penalties up to £3,000 per form. Mandatory payrolling of benefits starts 6 April 2027, so 2025-26 is the last full P11D year for most employers.
Who Has to File a P11D for 2025-26?
Any employer that provided a taxable benefit to a director or employee during 2025-26 must file. That includes company cars, fuel, private medical insurance, gym memberships, interest-free or low-interest loans above £10,000, accommodation, and anything else that is not exempt and was not already taxed through payroll.
If you registered with HMRC before 5 April 2025 to payroll benefits for 2025-26, you have already taxed most of them through your PAYE submissions. You still need to file a P11D(b) to report the total Class 1A NIC due, but you can skip the individual P11D forms for benefits you payrolled. Loans and accommodation always need a P11D, even if you payroll everything else. Anything sitting in a director's loan account above £10,000 at any point in the year is reportable as a beneficial loan.
In our experience, the trip-up here is the director who takes a private medical policy mid-year and forgets the company is the contracting party. That is a P11D benefit, full stop, and a common reason small companies miss returns.
What Is the Class 1A NIC Rate for 2025-26?
The Class 1A rate is 15% on the total cash equivalent of benefits reported on the P11D(b) (HMRC CWG5, 2025). That is up from 13.8% in 2024-25, matching the headline employer NIC rise that took effect 6 April 2025.
On a £100,000 benefits bill that is the difference between £13,800 and £15,000, so a £1,200 swing. Bigger employers with significant car fleets or private medical schemes are seeing a meaningful jump in the Class 1A line this year. Class 1A is an employer-only cost. Employees do not contribute to it, but they still pay income tax on the cash equivalent through their PAYE code.
When Are the Payment Deadlines?
The P11D and P11D(b) filing deadline is 6 July 2026. The Class 1A NIC payment falls a fortnight later:
- 19 July 2026 if you pay by cheque (must reach HMRC by that date, not just be posted)
- 22 July 2026 if you pay electronically by Faster Payments, BACS, or CHAPS
HMRC charges late-payment interest from the day after the deadline. The current rate sits at base plus 4 percentage points, which is the highest premium HMRC has ever charged on overdue tax. If your reference quotes the wrong period or you send the payment to the wrong account, you will still get hit with interest while the matter is sorted.
What Happens If You Miss the 6 July Deadline?
The P11D(b) late filing penalty is £100 per 50 employees for each month (or part-month) the return is late (BDO, 2025). A company with 80 employees that files three months late is looking at £600 in penalties on top of the interest on the Class 1A bill.
After four months, HMRC can also issue penalty notices. Persistent failure to file can escalate further, and HMRC compliance teams have been more active on P11D non-filers in the last two years. What we see most often is the employer who genuinely forgot rather than ignored it. The penalty does not care which.
For genuinely incorrect returns rather than late ones, the penalty regime is harsher. The maximum penalty for submitting an incorrect P11D is £3,000 per form (ACCA, 2025), though disclosure of a mistake before HMRC prompts you cuts that significantly. The lesson is to file what you have on time, even if you suspect a number, and amend later if needed.
How Do You Submit the P11D Now?
Online only. Paper P11D forms have not been accepted since 6 April 2023. You file through commercial payroll software, HMRC's PAYE Online for Employers service, or your accountant's filing software. There is no postal route any more, even for amendments.
Most modern payroll platforms (BrightPay, Xero, Sage, IRIS) generate the P11D directly from data you have already keyed in for benefits. The work is in making sure the cash equivalent calculation is right, especially for company cars where you need the list price, CO2 figure, fuel type, and any capital contribution from the employee.
If you find a mistake after filing, you submit a fresh amended P11D containing all benefits for that employee for the year, not just the corrected items. HMRC's online amendment service replaces the original return entirely.
What About Trivial Benefits and Things You Do Not Report?
Genuine trivial benefits stay off the P11D. The exemption covers benefits that cost £50 or less, are not cash or cash-equivalent vouchers, are not a reward for work done, and are not part of a contractual entitlement. A Christmas hamper, a birthday gift card for a high street store, a meal out for a team milestone, all fine within the £50 ceiling per item.
For directors of close companies the trivial benefits cap is £300 in total per tax year (GOV.UK, 2024) covering the director and any family or household members. If you ran six £50 gifts to the spouse of an owner-director over the course of the year, you have hit the ceiling. The seventh becomes reportable.
Other exemptions include workplace parking, certain mobile phones, business mileage paid at HMRC's approved rates, and qualifying childcare vouchers. The detail matters here. One question clients always ask is whether reimbursed expenses are reportable, and the answer for genuinely allowable business expenses is no, but only if there is a system in place to demonstrate they were business expenses.
Why 2025-26 Is the Last Full P11D Year
HMRC has confirmed that payrolling of most benefits in kind becomes mandatory from 6 April 2027 (Saffery, 2025). The original deadline was April 2026 but the change was delayed twelve months in April 2025 (Bishop Fleming, 2025), so employers have one more P11D cycle (2026-27) before the regime changes.
Once mandatory payrolling lands, income tax on benefits will be collected through the payroll in real time every pay period via your Full Payment Submission. Class 1A NIC will still need a separate P11D(b) and annual payment, but the individual P11Ds for most benefits disappear. Employment-related loans and accommodation are expected to remain on the P11D for a further phase, though final scope is still being consulted on.
HMRC's registration window for mandatory 2027-28 payrolling is expected to open in November 2026. Many employers will use the 2026-27 year to dry-run the process voluntarily so the mandatory switch is not a shock to payroll teams. If your business carries any meaningful benefits load, this autumn is the right time to look at your payroll provider's roadmap. We cover related employer-side support across our payroll and PAYE services.
Frequently Asked Questions
Do I need to file a P11D(b) if I have payrolled all my benefits?
Yes. The P11D(b) reports the total Class 1A NIC liability, and you still need to file it and pay the Class 1A by the relevant July deadlines even when individual benefits have been taxed through payroll. The only employers who escape the P11D(b) are those that provided no taxable benefits at all in the year.
What is the Class 1A NIC rate for the 2025-26 P11D(b)?
15%, applied to the total cash equivalent of benefits. This took effect from 6 April 2025 and replaces the previous 13.8% rate. The rate for 2026-27 stays at 15% based on current rates.
Can I still register to payroll benefits for 2026-27?
No, voluntary registration for the 2026-27 tax year closed on 5 April 2026. You can register from November 2026 for the mandatory 2027-28 regime when HMRC opens the window. For 2026-27 itself, anyone not already registered will need to file P11Ds the traditional way one more time.
How do I correct a P11D if I find an error after submitting?
Submit an amended P11D online for the affected employee containing all of their benefits for the year, not just the corrected items. The amendment replaces the original entirely. Disclose the mistake to HMRC before they prompt you to reduce any incorrect return penalty, which can otherwise reach £3,000 per form.
What is the penalty if I file the P11D late?
£100 per 50 employees for every month (or part-month) the return is late, plus interest on any underlying Class 1A NIC that misses the 19 or 22 July payment deadline. Persistent late filing can attract larger penalties and HMRC compliance attention.
Need a hand getting your 2025-26 P11D returns and Class 1A NIC bill sorted before 6 July, or want to talk through what mandatory payrolling means for your business from April 2027? Get in touch - we work with UK employers across payroll, benefits in kind, and PAYE compliance and can run the numbers with you.