P11D deadline 2026: what employers need to submit and by when

The 2025/26 P11D deadline falls on 6 July 2026. For employers still reporting employee benefits annually, this is the key date in the compliance calendar for the current tax year.

If you are an SME, please note that early planning is essential to avoid disruption and ensure systems and processes are ready.

Key points about the 2025/26 P11D deadline

Business should make sure to:

• submit P11D forms to HMRC by 6 July 2026
• provide employees with copies of their benefits information by 6 July 2026
• submit the P11D(b) declaration by 6 July 2026
• pay any Class 1A National Insurance due by 22 July 2026 if paying electronically.

Common areas where employers fall behind

• incomplete or late data from benefit providers (fleet, medical insurance, fuel cards)
• gaps between HR, payroll and finance on which benefits were provided and to whom
• miscalculating the taxable value of benefits, particularly company cars and vans
• missing the Class 1A National Insurance payment deadline separately from the P11D submission deadline.

Penalties for late or incorrect submissions

HMRC can charge penalties for P11D forms submitted after the deadline, and interest accrues on Class 1A National Insurance paid late. Persistent or repeated errors can also draw closer scrutiny of a business's wider payroll and benefits reporting.

Practical steps to take before 6 July

• confirm which benefits were provided during 2025/26 and to which employees
• reconcile benefit provider data against payroll and finance records
• check calculations for company car and van benefit values, including any changes in list price or CO2 bands
• issue employees with their benefits information alongside the HMRC submission
• diarise the 22 July Class 1A National Insurance payment separately from the P11D deadline.

The mandatory payrolling of Benefits in Kind

P11D reporting itself is changing. HMRC is moving toward mandatory payrolling of Benefits in Kind (BiK) from April 2027, which will shift much of this reporting into real-time payroll rather than an annual return. 

We have covered what that means for employers, and how to start preparing, in another article: Changes to the mandatory payrolling of Benefits in Kind

How we can help

If you need support meeting the 6 July deadline, reconciling benefits data or reviewing your current P11D process, please get in touch with our employment tax team or speak with your usual UHY adviser.