The reminder, published on 23 October 2026, applies to customers required to complete Self Assessment returns for the period from 6 April 2025 to 5 April 2026. Filing early allows taxpayers to establish how much they owe, arrange payments and receive any refunds sooner. HMRC has also outlined the support available to those completing their returns.
HMRC Urges Taxpayers To File Before the January Deadline
According to HMRC’s official announcement, customers can complete and submit their returns through GOV.UK rather than waiting until January. The department says early submission gives people more time to budget for their tax bills and reduces the risk of missing the deadline.
Myrtle Lloyd, HMRC’s Chief Customer Officer, said: “The Self Assessment deadline is 100 days away so now is the ideal time to get ahead and file your tax return early.” She added that guidance and support were available through GOV.UK, advising customers to search for “file my Self Assessment” to begin the process.
People submitting a return for the first time must register with HMRC to obtain a Unique Taxpayer Reference. Those uncertain whether they need to file can use the government’s online checking service.
The GOV.UK guidance also states that anyone who has received a letter requesting a return must submit it by the deadline specified. People who believe they no longer need to complete Self Assessment must contact HMRC to explain their circumstances.
The deadline for paper returns is 31 October 2026, while online returns and outstanding tax payments are due by 31 January 2027. Customers receiving income through PAYE may also be able to have tax owed collected through their tax code if they file online before 30 December.
Additional Tax Rules and Support for Self Assessment Customers
HMRC has highlighted several requirements affecting particular groups of taxpayers, including those receiving winter heating payments, Child Benefit and income from cryptoassets.
According to the department, customers who received the 2025 Winter Fuel Payment, or Scotland’s Pension Age Winter Heating Payment, may find the amount automatically included in their online return.
Where the payment is missing, taxpayers must enter it themselves. Those with total income exceeding £35,000 will repay the payment through their Self Assessment tax bill. Around 300,000 customers liable for the High Income Child Benefit Charge will also have their or their partner’s Child Benefit payment details pre-populated in online returns.
Some customers can instead pay the charge monthly through their salary using HMRC’s PAYE digital service. Cryptoasset owners must declare taxable gains exceeding the £3,000 Capital Gains Tax allowance for the 2025 to 2026 tax year.
HMRC also confirmed that customers registered for Making Tax Digital for Income Tax must still submit their Self Assessment returns in the usual way. Support includes online guidance, instructional videos and a digital assistant. Customers can also seek assistance from tax agents, relatives or voluntary organisations. The department has warned taxpayers about criminals impersonating HMRC and advised against opening unexpected links or sharing sign-in details.
