This comprehensive planner brings together all key financial deadlines for the 2025/26 tax year in one place. It includes both employer obligations and self assessment deadlines, along with the necessary documents and submission requirements.
Save the dates from this table to stay organised and ensure timely compliance with HMRC.
Key Financial Deadlines and Required Documents
April 2025 |
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Type |
Date |
What’s Due |
Documents Required |
| Employer | 19 April 2025 | Final PAYE return for 2023/24. Interest begins on unpaid PAYE, NICs, Student Loans or CIS for 2024/25. Penalties may apply. | Final FPS and/or EPS for 2023/24; proof of payments for 2024/25. |
May 2025 |
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Type |
Date |
What’s Due |
Documents Required |
| Employer | 3 May 2025 | Submit P46(Car) for changes during the quarter ending 5 April 2025. | P46(Car) |
| Employer | 18 May 2025 | PAYE, Student Loan and CIS deductions due for month ending 5 May. | RTI submissions and payment confirmation |
| Employer | 31 May 2025 | Issue P60s to all employees for the 2024/25 tax year. | P60 for each employee employed on 5 April 2025 |
June 2025 |
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Type |
Date |
What’s Due |
Documents Required |
| Employer | 1 June 2025 | New Advisory Fuel Rates (AFR) apply. | Internal mileage and reimbursement documentation |
| Employer | 19 June 2025 | PAYE, Student Loan and CIS deductions due for month ending 5 June. | Payroll records and payment confirmations |
July 2025 |
|||
Type |
Date |
What’s Due |
Documents Required |
| Employer | 5 July 2025 | Deadline to apply for PAYE Settlement Agreement (PSA) for 2024/25. | PSA application |
| Employer | 6 July 2025 | Submit P11D and P11D(b) to HMRC; issue copies to employees. | P11D for each employee, P11D(b) summary |
| Employer | 19 July 2025 | PAYE, Student Loan and CIS deductions due for month ending 5 July. | RTI submissions and payment confirmation |
| Employer | 19 July 2025 | Class 1A NICs due for 2024/25. | Class 1A NICs payment reference from P11D(b) |
| Self Assessment | 31 July 2025 | Deadline for second payment on account for the 2024/25 tax year (if applicable). | Confirmation of first payment made and calculation of second instalment. |
August 2025 |
|||
Type |
Date |
What’s Due |
Documents Required |
| Employer | 2 August 2025 | Submit P46(Car) for changes during the quarter ending 5 July. | P46(Car) |
| Employer | 19 August 2025 | PAYE, Student Loan and CIS deductions due for month ending 5 August. | Payroll records and payment confirmations |
September 2025 |
|||
Type |
Date |
What’s Due |
Documents Required |
| Employer | 1 September 2025 | New Advisory Fuel Rates apply. | Expense claim forms and mileage logs |
| Employer | 19 September 2025 | PAYE, Student Loan and CIS deductions due for month ending 5 September. | Payroll reports and payment evidence |
October 2025 |
|||
Type |
Date |
What’s Due |
Documents Required |
| Self Assessment | 5 October 2025 | Deadline to register for Self Assessment for 2024/25 OR to notify HMRC of new income, capital gains, or HICBC liability if no return has been issued. | Personal details, NI number, and relevant income/gain information. |
| Employer | 19 October 2025 | Tax and NICs due under the 2024/25 PAYE Settlement Agreement. | PSA confirmation and payment details |
| Self Assessment | 31 October 2025 | Deadline to submit paper Self Assessment tax return for 2024/25. | Completed SA100 and any supplementary pages. |
November 2025 |
|||
Type |
Date |
What’s Due |
Documents Required |
| Employer | 2 November 2025 | Submit P46(Car) for changes during the quarter ending 5 October. | P46(Car) |
| Employer | 19 November 2025 | PAYE, Student Loan and CIS deductions due for month ending 5 November. | Payroll and payment records |
December 2025 |
|||
Type |
Date |
What’s Due |
Documents Required |
| Employer | 1 December 2025 | New Advisory Fuel Rates apply. | Internal reimbursement templates and mileage policies |
| Employer | 19 December 2025 | PAYE, Student Loan and CIS deductions due for month ending 5 December. | RTI submissions and payment records |
| Self Assessment | 30 December 2025 | Deadline to submit online Self Assessment return if you want tax collected via PAYE (and are eligible). | Online Self Assessment return and relevant income details. |
January 2026 |
|||
Type |
Date |
What’s Due |
Documents Required |
| Employer | 19 January 2026 | PAYE, Student Loan and CIS deductions due for month ending 5 January. | Payroll reports and payment confirmations |
| Self Assessment | 31 January 2026 | Final deadline to file online Self Assessment return and pay tax due for 2024/25. First payment on account for 2025/26 also due. | Online return, tax calculation, and payment. |
February 2026 |
|||
Type |
Date |
What’s Due |
Documents Required |
| Employer | 2 February 2026 | Submit P46(Car) for changes during the quarter ending 5 January. | P46(Car) |
| Employer | 19 February 2026 | PAYE, Student Loan and CIS deductions due for month ending 5 February. | RTI reports and proof of payment |
March 2026 |
|||
Type |
Date |
What’s Due |
Documents Required |
| Employer | 1 March 2026 | New Advisory Fuel Rates apply. | Company car reimbursement documentation |
| Employer | 19 March 2026 | PAYE, Student Loan and CIS deductions due for month ending 5 March. | Payroll reports and payment records |
Stay Ahead with Expert Support
Meeting financial deadlines and managing the documentation can be time-consuming, especially when you’re focused on running your business. At Haines Watts, we help business owners, property managers and individuals keep compliant and financially efficient all year round.
