The Complete UK Tax Month and Tax Week Calendar Guide for Payroll Professionals (2025-2026)

For businesses operating in the United Kingdom, maintaining compliance with HMRC payroll regulations requires a thorough understanding of how the UK tax year is structured. Whether your organization processes weekly, fortnightly, four-weekly, or monthly payroll, properly aligning your payment schedules with HMRC’s tax week and tax month system is essential for accurate reporting and timely payments.

This comprehensive guide explains the structure of tax periods in the 2025-2026 tax year, provides detailed instructions on interpreting the official HMRC calendar, and offers practical advice on meeting PAYE reporting and payment deadlines based on your payroll frequency.

UK tax year 2025–2026: core information

Tax year timeline

The 2025-2026 UK tax year officially begins on Sunday, 6 April 2025 and concludes on Sunday, 5 April 2026. During this period, HMRC organizes the fiscal calendar into:

• 52 tax weeks (occasionally 53 in certain years), with each week beginning on Monday and ending on Sunday
• 12 tax months, with each month starting on the 6th and ending on the 5th of the following month

This structured framework establishes the official deadlines for PAYE submissions and determines which tax period each payroll cycle belongs to – critical information for compliance purposes.

Understanding tax periods: weeks and months

While standard calendar periods are familiar concepts, HMRC defines tax periods according to its own specific parameters. Here’s a detailed breakdown:

Tax weeks explained

A tax week runs from Monday to Sunday, creating a consistent seven-day cycle throughout the tax year:

• Week 1: Monday, 7 April 2025 to Sunday, 13 April 2025
• Week 2: Monday, 14 April 2025 to Sunday, 20 April 2025
• This pattern continues sequentially through Week 52 (or occasionally Week 53)

Tax months explained

Unlike calendar months, tax months begin on the 6th of each month and end on the 5th of the following month:

• Tax Month 1: 6 April 2025 – 5 May 2025
• Tax Month 2: 6 May 2025 – 5 June 2025
• Tax Month 3: 6 June 2025 – 5 July 2025
• This pattern continues through Tax Month 12 (6 March 2026 – 5 April 2026)

These specially defined periods form the foundation of the PAYE system. The specific date an employee receives payment determines which tax week or month their earnings fall into – and consequently, when your organization must submit reports and payments to HMRC.

How payroll frequency impacts tax reporting deadlines

Your organization’s payroll frequency directly determines which elements of the tax calendar you need to follow most closely.

Weekly payroll

For organizations operating weekly payroll cycles:

• Each pay run corresponds precisely to one tax week
• Example: If your standard payday is Friday, a payment made on Friday, 11 April 2025 falls within tax week 1 (7-13 April 2025)
• FPS submissions must be made on or before each payday
• PAYE liabilities are typically aggregated and paid monthly

Fortnightly payroll

For businesses paying employees every two weeks:

• Each pay cycle spans two consecutive tax weeks
• Most organizations reference the second week in each pair when assigning the appropriate tax period
• Example: A pay period covering 7-20 April 2025 spans tax weeks 1 and 2, with reporting typically aligned to week 2
• FPS submissions must still be made on or before each payday

Four-weekly payroll

For organizations operating on four-week payment cycles:

• Each pay run encompasses four consecutive tax weeks
• To identify the correct tax period for reporting purposes, check which tax month contains the final day of your four-week cycle
• Example: If your four-week pay period ends on 4 May 2025, it falls within tax month 1 (6 April-5 May 2025)
• This information determines your submission deadlines and payment due dates

Monthly payroll

For businesses processing monthly payroll:

• Monthly pay runs should follow HMRC’s tax months rather than calendar months
• Each tax month begins on the 6th and concludes on the 5th of the following month
• Example: If you pay employees on the 28th of each month, a payment on 28 April 2025 falls within tax month 1 (6 April–5 May 2025)
• FPS submissions are required on or before each monthly payday

Correctly matching your specific pay dates to these official tax periods establishes the appropriate submission and payment deadlines for your organization.

Navigating the HMRC tax calendar effectively

HMRC’s downloadable tax calendar is an invaluable resource for payroll professionals seeking to identify submission and payment deadlines based on their specific payroll frequency. Each payment schedule aligns with distinct tax periods, which in turn determine when earnings must be reported and when tax liabilities must be settled.

Weekly payroll calendar alignment

Each weekly payday corresponds to one of the 52 (occasionally 53) tax weeks in the year:

• Tax Week 1: Monday, 7 April 2025 – Sunday, 13 April 2025
• Tax Week 2: Monday, 14 April 2025 – Sunday, 20 April 2025
• This pattern continues throughout the tax year

Weekly payroll requires careful tracking of which tax week each payday falls into, particularly when months transition or around bank holidays.

Fortnightly payroll calendar alignment

Fortnightly payment cycles cover two consecutive tax weeks:

• Most organizations report these by using the second of the two weeks as the reference point
• Example: A pay period spanning 7-20 April 2025 would be reported with reference to tax weeks 1 and 2
• This approach maintains consistency with HMRC’s expectations for reporting

Four-weekly payroll calendar alignment

These payment cycles span four consecutive tax weeks:

• Typically mapped to a single tax month for reporting purposes
• Example: If your pay period concludes on 3 May 2025, it belongs to tax month 1 (6 April-5 May 2025)
• The end date of each four-week cycle is particularly important for determining the correct tax period

Monthly payroll calendar alignment

Monthly payments follow HMRC’s tax month structure:

• Tax Month 1: 6 April 2025 – 5 May 2025
• Tax Month 2: 6 May 2025 – 5 June 2025
• Tax Month 3: 6 June 2025 – 5 July 2025
• This continues through Tax Month 12, ending on 5 April 2026

To maintain compliance, carefully match each payment date to its corresponding tax period and use this information to schedule FPS submissions and PAYE payments appropriately. Aligning your internal payroll systems with HMRC’s tax structure guarantees accurate reporting and helps avoid costly late-filing penalties.

PAYE reporting and payment deadlines: detailed requirements

HMRC mandates that employers report and pay all payroll deductions according to strict timelines. These deductions include income tax, National Insurance contributions (NIC), and student loan repayments.

Reporting requirements

Full Payment Submission (FPS) requirements:

• Must be submitted on or before the actual payment date to employees
• Contains comprehensive details of all payments made and deductions taken from each employee
• Late submissions may trigger automatic penalties
• Should include all employees paid during that period, even those below the Lower Earnings Limit

Payment deadlines

PAYE and NIC amounts must reach HMRC according to these deadlines:

• Electronic payments: Must be received by the 22nd of the month following the tax month in which the payments were made
• Postal payments: Must be received by the 19th of the following month (though this method is increasingly rare and not recommended due to potential delays)

For example:

• If you pay employees on 25 April 2025 (within tax month 1), electronic payment of the associated PAYE and NIC must reach HMRC by 22 May 2025
• For quarterly payers (small employers with average monthly PAYE/NIC liabilities below £1,500), special deadlines apply

Early planning is essential

To avoid potential penalties for late or incorrect submissions:

• Schedule your payroll processing with sufficient lead time
• Factor in bank holidays and weekends that might affect processing times
• Set calendar reminders for submission and payment deadlines
• Consider setting internal deadlines that are earlier than HMRC’s official deadlines

Managing a 53-week tax year

In certain years, weekly payrolls will encompass 53 tax weeks instead of the standard 52. This situation occurs when the final payday of the tax year falls on 5 April.

The 2025-2026 tax year

For the upcoming tax year:

• 5 April 2026 falls on a Sunday
• If your organization’s weekly payday is Sunday, you will need to process and report a 53rd week
• This may require adjustments to employee tax codes or personal allowance calculations

Most employers will not encounter this situation in the 2025-2026 tax year unless Sunday is their standard payday. However, it’s advisable to verify your calendar to ensure proper planning if this rare circumstance applies to your organization.

Critical deadlines for the 2025–2026 tax year

Mark these essential dates in your payroll calendar:

• 6 April 2025: Tax year officially begins
• 19 April 2025: Due date for postal PAYE payments for tax month 12 of previous tax year
• 22 April 2025: Due date for electronic PAYE payments for tax month 12 of previous tax year
• 31 May 2025: Deadline for issuing P60 forms to all employees
• 6 July 2025: Final date for submitting P11D and P11D(b) forms for 2024–2025 benefits and expenses
• 19 July 2025: Deadline for postal payments of Class 1A NIC on benefits
• 22 July 2025: Deadline for electronic payments of Class 1A NIC on benefits
• 5 April 2026: Tax year concludes
• 22nd of each month: Deadline for electronic payment of monthly PAYE liabilities
• 19th of each month: Deadline for postal payment of monthly PAYE liabilities (not recommended)

Practical tips for payroll compliance

To make sure your organization maintains full compliance with HMRC requirements:

1. Create a comprehensive payroll calendar. Develop a detailed calendar mapping your specific paydays to the corresponding tax weeks and months
2. Set automated reminders. Implement system notifications for upcoming submission and payment deadlines
3. Build in buffer time. Schedule internal deadlines 2-3 days before official HMRC deadlines to allow for unexpected delays
4. Regular calendar reviews. Review your payroll calendar quarterly to account for any changes in payment schedules or bank holidays
5. Staff training. Make sure all payroll staff understand how tax weeks and months work in relation to your specific payroll frequency
6. Maintain documentation. Keep detailed records of all submissions and payments for audit purposes
7. Consider software solutions. Utilize payroll solutions that automatically track tax periods and flag upcoming deadlines

Wallester Payroll Program: aligning technology with tax compliance

Managing payroll in line with HMRC tax calendars is challenging enough without the added complexity of manual payment processing, outdated banking systems, or delays in fund distribution. For companies seeking a more efficient and reliable approach, the Wallester Payroll Program offers a fully integrated solution tailored to the realities of modern payroll operations. Instead of relying on traditional bank transfers, employers can issue both virtual and physical Visa cards to their employees, enabling same-day salary payouts that align precisely with their chosen payroll frequency – whether weekly, fortnightly, four-weekly, or monthly.

Wallester’s system makes it easy to schedule and automate top-ups according to tax weeks or tax months, reducing the risk of late payments and easing the administrative burden on finance teams. Employers maintain full control through a centralized platform where they can monitor balances, adjust card limits, and access detailed transaction histories – all in real time. This improves transparency and simplifies reconciliation, especially when paired with accounting tools or internal compliance workflows.

The program is especially useful for businesses with distributed teams, variable work schedules, or tight payroll cycles that need to align precisely with HMRC’s reporting periods. Whether your priority is improving speed, accuracy, or control, Wallester provides the infrastructure to run payroll in a way that meets both employee expectations and regulatory obligations.

Conclusion

Understanding the structure of tax months and tax weeks is fundamental to operating payroll accurately and meeting all HMRC deadlines. Whether your organization processes payroll weekly, fortnightly, four-weekly, or monthly, each payment date must align correctly with the appropriate tax period.

By utilizing HMRC’s official tax calendars, planning submissions strategically, and scheduling payments according to the required timelines, your organization can avoid penalties and maintain seamless compliance throughout the 2025-2026 tax year.