Self Assessment Tax Return Deadline 2025 Uk. One of the most critical. Stay on top of your taxes with our comprehensive guide to the 2025/26 uk tax.
Anyone required to file a tax return for the 2023 to 2024 tax year who misses the 31 january 2025 deadline could face an initial late filing penalty of £100. You must register for self assessment by 5 october after the end of the tax.