A record 299,419 returns were filed in the first week of the new tax year, according to HM Revenue and Customs (HMRC).
People filling out self-assessment forms can submit their tax return for the 2024-25 tax year between April 6 2025, which was the first day of the new tax year, and the deadline for online returns on January 31 2026.
Paper tax returns must be submitted by October 31 2025.
HMRC said there were 57,815 “early filers” on the first day of the new tax year, which was a Sunday, compared with 67,870 people who filed on April 6 2024.
The revenue body is encouraging people to file early so they know what tax they owe sooner and can plan for any payments in advance.
People can set up a budget payment plan to make either weekly or monthly direct debit payments towards their self-assessment tax bill.
In cases where tax has been overpaid, refunds can be claimed as soon as the return has been processed and people can check if they are due a refund in the HMRC app, the revenue body said.
People should also watch out for scams by criminals pretending to be from HMRC and making fake refund offers.
