Key US/UK deadlines for 2025

The US tax year runs from January 1st to December 31st each year. For anyone subject to US tax systems, these are some of the deadlines and key dates for US tax filing that need to be considered throughout the tax period, wherever they are in the world. Below are some of the main deadlines for the 2024 US tax year.

January 15, 2025

Deadline for Individuals to pay Quarter 4 of 2024 Estimated Income Tax payment.

January 31, 2025

2023/24 UK Self-Assessment Deadline and Balancing Payment Due.

First payment on account for the 2024/25 UK tax year due.

March 6, 2025

Deadline for making a trust distribution under the 65-day election rules.

The 65-day rule means that any distribution made by an estate or trust during the first 65 days of the tax year can be treated as though it was paid on the last day of the previous tax year provided the election is timely made.

March 17, 2025

Deadline for S corporations (Form 1120-S) and Partnerships (Form 1065) to file their 2024 tax returns.

These filings are always due on the 15th day of the 3rd month after the close of a corporation’s or partnership’s tax year. If you need to request a six-month extension, the relevant extension forms for your situation would need to be filed.

Deadline for Owners of Foreign Trusts to file Form 3520-A (Annual Information Return of Foreign Trust with US Owner). A six-month extension can be claimed by filing Form 7004.

The deadline for a US owner who files on behalf of a trustee, i.e. a Substitute Form 3520-A will follow the individual’s Form 3520 Filing deadline.

April 5, 2025

Final day of the 2024-25 UK tax year.

April 15, 2025

Deadline for filing 2024 Individual Federal Income Tax Return Forms 1040/1040NR.

For individuals living outside of the US on April 15, 2024, an automatic extension is granted until June 16, 2025.

For individuals living in the US who require an extension, Form 4868 can be filed, which, if accepted, will allow you an additional six months to file your Individual Federal Income Tax Return.

For individuals who still owe tax for 2024, the final payment date is April 15, 2025, after which the amount owed will start to accrue interest and potential penalties.

Deadline for filing Form 709 US Gift tax return. An extension can be requested for an additional six months by filing Form 4868 (or Form 8892 if there is no Federal tax return filing requirement).

Deadline for Individuals to pay Quarter 1 of their 2025 Estimated Income Tax payment.

Deadline for filing 2024 FinCEN Form 114, Report of Foreign Bank and Financial Accounts (FBAR) form.

There is an automatic extension to October 15, 2025, to file the FBAR.

Deadline for filing the 2024 Corporation Income Tax return.

To request a six-month extension on filing your 2024 Corporation Income Tax return, you must file Extension Form 7004.

Deadline to file 2024 US Trust Form 1041. A five and a half month extension can be claimed by filing Form 7004.

Deadline for filing most 2024 Individual States’ Income Tax forms.

If an extension to submit your State Income Tax form is needed, please refer to the relevant state’s website for details on their extension criteria.

June 16, 2025

Deadline for filing 2024 Individual Federal Income Tax return for individuals residing outside the US as of April 15 and non-resident aliens who do not have a W-2 issued and do not have an office or place of business in the US

A four-month extension can be made by filing Form 4868.

Deadline for Individuals to pay Quarter 2 of their 2025 Estimated Income Tax payment.

July 31, 2025

Second payment on account due for the 2024/25 UK tax year.

September 15, 2025

Final extended deadline for S corporations (Form 1120-S) and Partnerships (Form 1065) to file 2024 tax returns.

Final extended deadline for Owners of Foreign Trusts to file Form 3520-A.

Deadline for Individuals to pay Quarter 3 of their 2024 Estimated Income Tax payment.

September 30, 2025

Final extended deadline for US Trusts to file Form 1041.

October 15, 2025

Final extended deadline for people living in the US filing 2024 Individual Federal Income tax return.

Final extended deadline for filing 2024 FBAR.

Final extended deadline for filing 2024 Foreign Trust Form 3520.

Final extended deadline for filing 2024 US Gift tax Form 709.

Final extended deadline for filing 2024 Corporation Income Tax return.

For those individuals living outside of the US, a two-month extension to file your Federal Income Tax return can be requested, which will extend until December 15, 2025. This must be done in writing to the IRS and approval is not automatic.

December 15, 2025

Final extended deadline for people living outside of the US and non-residents filing a 2024 Individual Federal Income Tax return.

December 30, 2025

If you have UK tax liabilities of less than £3,000, you can electronically file your tax return by this date and request that the tax be collected via a PAYE coding adjustment for the 2024/25 UK tax year.

December 31, 2025

End of the 2025 US tax year. This is the deadline for implementing any US tax year-end planning, such as making an upfront UK tax payment for FTC purposes.

Additional Timings to Consider:

• January 15, 2026 – Deadline for individuals to pay Q4 of 2025 Estimated Income Tax payment.
• January 31, 2026 – 2024/25 UK tax return electronic filing, balancing payment and 1st payment on account for the 2025/26  deadline.
• The standard due date for US Estate tax return Form 706/706-NA is nine months after the date of the decedent’s death. Form 4768 can extend the filing deadline by six months.

If you need assistance navigating your US tax obligations, we can help – wherever you are in the world. Contact us to find out more.