Transatlantic Tax Timeline 2024/25

It can be difficult & confusing for transatlantic businesses keep track of the US & UK tax filing & payment dates.

To help transatlantic business owners plan for the year ahead, we have prepared a calendar which details all the relevant US & UK corporate tax filing & payments dates in one place.

The US corporate tax return filing deadlines are determined in relation to the tax year end of the business.

While many US corporations use a calendar tax year, some may use a non-calendar tax year. The below US filing deadlines assume the US corporation uses a calendar tax year but details of the general rules are also included.

Generally, a US corporation must file its corporation tax returns & pay its tax liabilities by the 15th day of the 4th month following the end of the corporations tax year. A 6-month filing extension to file the tax return is available by request.

However, a US corporation with a June 30 year end must file its corporation tax returns & pay its tax liabilities by the 15th day of the 3rd month following the end of the corporation’s tax year. A 7-month filing extension to file the tax return is available by request.

A UK company must pay its tax liability within 9 months and 1 day of the end of its accounting period and file its tax return within 12 months of the end of its accounting period.