Tax Diary: February to March 2025 Deadlines That May Still Matter

This tax diary highlights key UK tax deadlines that fall between February and March 2025. It is relevant for taxpayers reviewing whether all obligations from this period were dealt with correctly.

Although some deadlines may have passed, unresolved filings or payments can still result in penalties, interest, or HMRC follow-up action, especially where the wider tax position was not reviewed at the time by a tax specialist in London.

Key Tax and Payroll Deadlines for February and March 2025

• 1 February 2025 – Due date for Corporation Tax payable for the year ended 30 April 2024.
• 19 February 2025 – PAYE and NIC deductions due for month ended 5 February 2025. (If you pay your tax electronically the due date is 22 February 2025)
• 19 February 2025 – Filing deadline for the CIS300 monthly return for the month ended 5 February 2025.
• 19 February 2025 – CIS tax deducted for the month ended 5 February 2025 is payable by today.
• 1 March 2025 – Due date for Corporation Tax due for the year ended 31 May 2024.
• 2 March 2025 – Self-Assessment tax for 2023-24 paid after this date will incur a 5% surcharge unless liabilities are cleared by 1 April 2025, or an agreement has been reached with HMRC under their time to pay facility by the same date.
• 19 March 2025 – PAYE and NIC deductions due for month ended 5 March 2025 (If you pay your tax electronically the due date is 22 March 2025).
• 19 March 2025 – Filing deadline for the CIS300 monthly return for the month ended 5 March 2025.
• 19 March 2025 – CIS tax deducted for the month ended 5 March 2025 is payable by today.

Why February and March Deadlines Still Matter

Tax obligations do not fall away once a deadline passes. Where a return was not filed or a payment was not made on time, the issue remains open until it is resolved.

For many taxpayers, this period follows the January Self Assessment deadline, when outstanding matters may begin to attract further charges or HMRC attention.

Common Obligations Around February and March

Deadlines during this period often relate to:

• Outstanding Self Assessment filing or payment issues
• VAT return submissions and payments
• PAYE and National Insurance reporting and payments
• Ongoing compliance and reporting obligations

Which obligations applied will depend on your circumstances, such as whether you were self-employed, a landlord, an employer, or VAT-registered and how closely ongoing matters were monitored by a tax specialist in London or similar professional support.

What Happens If a Deadline Was Missed?

If a tax deadline in February or March 2025 was missed, HMRC may have applied penalties or charged interest from the original due date.

In some cases, penalties increase the longer an issue remains unresolved. Even where no immediate notice was issued, HMRC may still pursue the matter later.

Why It Is Worth Reviewing Now

Some taxpayers assume that once the January deadline has passed, any remaining issues are minor. In practice, unresolved obligations can escalate and become more costly over time.

Reviewing whether all February–March 2025 obligations were met can help prevent unexpected demands or enforcement action later in the tax year.

HMRC Guidance on Late Tax Deadlines

HMRC explains how penalties and interest apply to late filings and payments on
GOV.UK.

Did You Miss Any February or March 2025 Deadlines?

Whether any action is required now will depend on which obligations applied to you at the time and whether they were dealt with correctly. For individuals and businesses in Farringdon and nearby areas such as Liverpool Street and Finsbury, CIGMA Accounting can review your position and confirm whether anything remains outstanding or needs to be addressed.