Self Assessment: Child Benefit pre-filled on 300,000 returns

What is new this year: 300,000 Child Benefit records filled in

HM Revenue and Customs set out the change in its reminder published on 8 October 2026. Around 300,000 customers who pay the High Income Child Benefit Charge through Self Assessment will have their or their partner's Child Benefit payment details filled in on their online tax return. The pre-population is intended to reduce the amount of information those customers need to enter themselves when they complete the return for the 2025 to 2026 tax year.

Some customers may be able to pay the High Income Child Benefit Charge monthly through their salary using HMRC's PAYE digital service, which amends their tax code. That option sits alongside the existing route of paying the charge through Self Assessment. The charge applies to customers whose income exceeds the threshold and who receive Child Benefit, or whose partner receives it. The pre-filled figure covers the Child Benefit payment details, and customers remain responsible for checking that the information on the return is correct before it is submitted.

The Self Assessment deadlines for 2025 to 2026

The deadline for paper Self Assessment tax returns for the 2025 to 2026 tax year is 31 October 2026. The deadline to submit an online Self Assessment tax return and pay any tax due for the 2025 to 2026 tax year is 31 January 2027. Customers who file on paper therefore have less time to complete the return than those who file online, and the two dates apply to the same tax year.

Self Assessment customers with PAYE income can file online before 30 December and have any tax owed collected through their tax code. That route moves the collection of the tax into the payroll process rather than requiring a separate payment by 31 January 2027. The 30 December date is earlier than the standard online filing and payment deadline, and it applies only where the customer has PAYE income and wants the tax collected through the tax code. Customers who do not use that option pay any tax owed by 31 January 2027.

Winter Fuel Payment and your tax return

Customers who received the 2025 to 2026 Winter Fuel Payment, or the Pension Age Winter Heating Payment in Scotland, and are in Self Assessment will see the payment filled in on their online return where possible. Customers should check the Winter Fuel Payment entry and add it manually if it is not shown. Paper filers need to add it themselves, because the pre-population applies to online returns.

Customers with a total income over 35,000 pounds pay the Winter Fuel Payment back through their Self Assessment tax bill. The repayment is handled through the tax return rather than through a separate process. Customers in Scotland can opt out of the Pension Age Winter Heating Payment by midday on 19 October 2026. The opt out date falls before the 31 October 2026 paper filing deadline and before the 31 January 2027 online deadline.

Making Tax Digital customers still file a return

Customers signed up to Making Tax Digital for Income Tax still need to submit their Self Assessment tax return and pay any tax owed by 31 January 2027. Being signed up to Making Tax Digital for Income Tax does not remove the requirement to complete a Self Assessment return for the 2025 to 2026 tax year. The 31 January 2027 date applies to both the submission of the return and the payment of any tax owed.

The reminder covers customers who have joined Making Tax Digital for Income Tax as well as those who have not. The same online filing and payment deadline applies to both groups. Customers in this position should not treat their Making Tax Digital for Income Tax sign up as a substitute for the Self Assessment return, and the tax owed for the 2025 to 2026 tax year remains payable by 31 January 2027.

What HMRC says about starting early

An HMRC-commissioned survey of more than 5,200 customers found more than 26% said they experience anxiety when tax or financial deadlines are approaching. HMRC also said more than 24,000 customers filed their return on World Mental Health Day last year. The figures were published alongside the reminder on 8 October 2026 and relate to the customer experience of approaching deadlines.

HMRC's suggested steps are: have records and income details to hand, start the return and save it to return later, take time to make it accurate, and plan how to pay any tax owed. Anyone unsure whether they need to file can use the Self Assessment checker tool on GOV.UK, where they can also tell HMRC they no longer need to complete a return. The checker tool and the option to tell HMRC that a return is no longer needed are both available on GOV.UK.

Source: HMRC press release, 8 October 2026.

Related coverage on Kael Tripton: Self Assessment: register by 5 October or face a penalty, HMRC July 2026 Self Assessment Deadline: Second Payment on Account Due 31 July, Self Assessment Tax Return UK 2025/26: Deadlines, Who Must File and How to Submit, Late Inheritance Tax Return UK: Penalties, Interest and How to Appeal, Winter Fuel Payment went to 10.9 million pensioners after U-turn.

Frequently asked questions

When is the paper Self Assessment deadline for the 2025 to 2026 tax year?

The deadline for paper Self Assessment tax returns for the 2025 to 2026 tax year is 31 October 2026.

When is the online Self Assessment deadline and payment deadline?

The deadline to submit an online Self Assessment tax return and pay any tax due for the 2025 to 2026 tax year is 31 January 2027.

How many customers will have Child Benefit details filled in on their online return?

Around 300,000 customers who pay the High Income Child Benefit Charge through Self Assessment will have their or their partner's Child Benefit payment details filled in on their online tax return.

Can the High Income Child Benefit Charge be paid through salary?

Some customers may be able to pay the High Income Child Benefit Charge monthly through their salary using HMRC's PAYE digital service, which amends their tax code.

What happens with the Winter Fuel Payment on a tax return?

Customers who received the 2025 to 2026 Winter Fuel Payment, or the Pension Age Winter Heating Payment in Scotland, and are in Self Assessment will see the payment filled in on their online return where possible. Customers should check the entry and add it manually if it is not shown. Paper filers need to add it themselves. Customers with a total income over 35,000 pounds pay the Winter Fuel Payment back through their Self Assessment tax bill.