For many owner-managed businesses, the P11D form sits in the ‘I’ll deal with it later’ pile — right until July arrives and the deadline is suddenly imminent. That’s understandable. It’s one of those payroll obligations that doesn’t come up every month, so it’s easy to underestimate how much is involved.

The P11D is the form employers use to report benefits in kind — any non-cash perks provided to directors or employees that haven’t been taxed through payroll. Think company cars, private health insurance, interest-free loans, and similar arrangements. HMRC uses this information to make sure the right amount of Income Tax and National Insurance is collected.

What makes 2026 particularly important is that the way employers report benefits in kind is changing fundamentally. Mandatory payrolling of most benefits comes into effect from April 2026, which means the traditional P11D process as we know it will eventually become obsolete. But for the 2025-26 tax year, the deadline of 6 July 2026 still applies — and the penalties for missing it are real.

A P11D is a form employers submit to HMRC each year to declare the cash equivalent value of any benefits or expenses provided to directors and employees earning £8,500 or more annually. A separate P11D is required for each individual who received a benefit.

Common benefits that need reporting include:

• Company cars and fuel for private use
• Private medical or dental insurance
• Interest-free or low-interest loans above £10,000
• Non-business travel and entertainment expenses
• Subscriptions and professional fees paid by the employer
• Accommodation provided by the employer

There’s also the P11D(b) — a separate but related form that declares the total amount of Class 1A National Insurance Contributions (NICs) the employer owes on those benefits. This is the form that calculates the employer’s NIC liability, and it needs to be submitted even if you have a PAYE settlement agreement in place.

It’s worth being clear that not everything counts. Genuinely business-related expenses, trivial benefits within the £50 exemption, and benefits covered by a dispensation or exemption notice don’t need to appear on the form. Getting that distinction right is where a lot of employers trip up.

The filing deadline for the P11D and P11D(b) for the 2025-26 tax year is 6 July 2026. That’s the date by which both forms must be submitted to HMRC, and it’s also the date by which any amounts the employee has made good (i.e. repaid to the employer) can still be entered on the form to reduce the taxable benefit.

Miss that deadline and the consequences escalate quickly:

• P11D(b) late submission: an automatic penalty of £100 per 50 employees for each month or part-month the form is late.
• Late P11D per employee: HMRC can pursue a penalty of up to £300 per form through the First-tier Tax Tribunal, plus £60 per day for continued non-compliance.
• Late Class 1A NIC payment: the deadline to pay is 22 August 2026. A 5% surcharge applies after that date, rising to 10% after six months and 15% after twelve months.
• Interest on late tax: HMRC will charge interest on any unpaid amounts from the due date.

One more thing worth flagging: since April 2023, HMRC no longer accepts paper amendments to P11D or P11D(b) forms. All corrections must be made using HMRC’s online service, and the maximum penalty for submitting an incorrect P11D is £3,000 per form. If you’ve discovered historical errors, a voluntary disclosure to HMRC is usually the more sensible route than trying to amend old forms.

This is the change that every employer providing benefits needs to understand. From April 2026, mandatory payrolling of benefits in kind applies. Instead of reporting benefits annually on a P11D after the tax year ends, most employers will be required to report them in real time through the Full Payment Submission (FPS) — the same submission used for regular payroll.

The practical effect is that employees’ tax on benefits will be collected during the year through PAYE, rather than being adjusted retrospectively. HMRC estimates this will affect around four million people who currently have their Income Tax collected in arrears — often leading to surprise tax bills or unexpected underpayments.

Two categories are being treated differently initially: employment-related loans and employer-provided accommodation will not be mandated at this stage, though voluntary payrolling of these will be available from April 2026.

For businesses already using payroll software, the transition means configuring benefits correctly within your payroll system. For those still running manual processes, it’s a strong signal that cloud payroll software is no longer optional.

The 2025-26 tax year (ending April 2026) is effectively the last full year where the traditional P11D route applies as standard. After that, most benefits need to flow through payroll in real time. If you haven’t yet spoken to your accountant or payroll provider about how this affects your business, the time to do that is now — not in October.

Alongside the payrolling change, April 2026 brought some welcome relief for employers offering certain workplace benefits. From 6 April 2026, tax and National Insurance exemptions have been extended to cover:

• Reimbursed eye tests for display screen equipment users
• Flu vaccinations provided or reimbursed by the employer
• Homeworking equipment provided to employees working from home

These exemptions mean qualifying expenditure no longer needs to be reported on a P11D or payrolled as a benefit, which removes a layer of admin for employers who offer these perks.

It’s a small but meaningful acknowledgement that the benefits-in-kind system has historically captured some genuinely non-taxable perks in its net. If you’ve been including these in your annual reporting out of caution, it’s worth reviewing whether they still need to appear at all.

We’d also note that the Small Employers’ Relief compensation rate increased to 9% from April 2026 (up from 8.5%), which is worth factoring into your NIC calculations if your business qualifies for that relief. These aren’t headline-grabbing changes, but in aggregate they do affect what you owe and what you need to report.

For the 2025-26 tax year, P11D and P11D(b) must be submitted through HMRC’s PAYE Online service or via commercial payroll and accounting software. Paper forms are only permitted in very limited circumstances — specifically if the business has ceased trading or is formally recognised as digitally exempt. For the vast majority of employers, digital submission is the only route.

In practice, most payroll software will have a P11D module or workflow. If you’re using Xero, QuickBooks, or a dedicated payroll tool, the forms can usually be compiled and submitted directly without needing to log into HMRC separately. The key is making sure all benefit values are correctly entered and reconciled before submission.

From April 2026 onwards, under the new mandatory payrolling rules, benefits will instead flow through the FPS alongside regular payroll. That means your payroll software needs to be capable of handling benefit values per employee — and many standard small-business payroll setups will need updating or configuring properly to handle this.

If your payroll is currently handled in-house using a spreadsheet or a basic tool, this transition is a good moment to revisit whether that setup is still fit for purpose. The Real Time Information (RTI) system already requires digital payroll submissions for most employers — payrolling benefits is simply the next step in that same direction of travel.