The short answer
How to check HMRC’s pre-populated Child Benefit figures in Self Assessment, correct missing information and decide whether PAYE can collect the charge.
HMRC has introduced the pre-population of Child Benefit information in online Self Assessment returns. The information comes from records HMRC already holds and is intended to make the High Income Child Benefit Charge easier to report and reduce missed or late entries.
Pre-population is a starting point, not a confirmation that the figure is correct. When the Child Benefit section appears in your return, compare it with the Child Benefit actually received for the relevant year. If the figures are wrong, amend them and provide the explanation requested by the return. If HMRC does not hold all the relevant payment information, complete the section manually.
This page focuses on the filing workflow. For the charge calculation, see the High Income Child Benefit Charge 2026/27 guide. For rates, eligibility and the claim itself, see the Child Benefit UK 2026/27 guide.
Pre-population is not automatic approval
Correct figures need an explanation
Missing data still needs manual entry
What does HMRC pre-populate?
HMRC says its online Self Assessment return can pre-populate Child Benefit information using data it already holds. The purpose is to help the High Income Child Benefit Charge be calculated correctly and reported on time. Around 300,000 Self Assessment customers are expected to benefit from the change, including cases where the relevant Child Benefit was received by the customer or their partner.
The pre-populated figure is an information transfer from HMRC records. It does not change who is responsible for checking the return, and it does not decide which partner is the higher earner for the charge. The charge is based on the relevant adjusted net income rules, not simply on whose name appears in the Child Benefit record.
How to check the Child Benefit section
Before submitting the return, compare the pre-populated details with:
- Child Benefit payment records or bank statements;
- the date the claim started or ended;
- any periods when payment was paused or repaid;
- the person who received the Child Benefit; and
- the tax year shown by the return.
Check both the amount and the period. A figure can be wrong because a claim started or stopped during the year, payment details were updated late, a partner’s information was not matched, or HMRC does not have a complete record.
Do not copy a figure from a different tax year. The 2025/26 amount reported in the 2026/27 filing cycle is separate from the Child Benefit paid during 2026/27.
What if the pre-populated figure is wrong?
Amend the figure in the online return and provide the requested explanation. The explanation should identify the difference clearly, for example a missing period, an amount paid after a claim change, a duplicate entry or a payment received by the other partner.
Keep the evidence that supports the correction. HMRC may need to understand why the return differs from its records, and a clear contemporaneous note is easier to verify than a later reconstruction.
If the underlying Child Benefit record is wrong, correct the return as required and separately use the appropriate Child Benefit or HMRC contact route to resolve the source record. Changing the Self Assessment figure does not necessarily update the Child Benefit claim itself.
What if information is missing?
HMRC says that where it does not hold all the relevant payment information, the Child Benefit section must be completed manually. Use your own payment records and confirm the amount for the tax year before submitting.
Manual completion does not mean the charge is optional. It means the return cannot rely on HMRC’s incomplete pre-populated data. If the records are unclear, resolve the payment history before filing or explain the uncertainty through the appropriate HMRC route.
Who reports the High Income Child Benefit Charge?
The charge normally applies to the higher earner in a household where adjusted net income is above the applicable threshold and Child Benefit has been received. The higher earner may be the person who claimed Child Benefit, their partner or another person in the household depending on the facts.
This is why a pre-populated Child Benefit figure does not, by itself, determine the final charge. You still need to check the higher earner’s adjusted net income, the Child Benefit received and any relevant reliefs or income adjustments.
Use the HICBC Calculator for an indicative estimate only. It cannot inspect your HMRC return or verify the pre-populated figure.
Can PAYE collect the charge instead?
Some people who are required to pay the High Income Child Benefit Charge may be able to ask HMRC to collect it through their tax code rather than reporting and paying it through Self Assessment. HMRC’s PAYE route has eligibility and timing conditions, and it is not automatically available to every person with Child Benefit income.
Check the official PAYE option before changing your filing route. If you are required to file Self Assessment for another reason, switching the Child Benefit charge to PAYE does not remove the wider Self Assessment obligation. If you complete a return solely to pay the charge, HMRC’s current guidance may provide a different route, but confirm it for the relevant year.
Do not use both PAYE collection and a Self Assessment charge for the same liability. The return, tax code and HMRC record should be consistent.
Common mistakes with pre-populated data
| Mistake | Why it matters | Safer approach |
|---|---|---|
| Submitting without checking the figure | HMRC data may be incomplete or out of date | Compare it with payment records |
| Assuming the claimant is always the liable person | HICBC uses the higher earner’s position | Check both partners’ adjusted net income |
| Amending without an explanation | HMRC asks for the reason when figures change | Record the period and reason for the correction |
| Using the wrong tax year | Child Benefit amounts vary by payment period | Reconcile the exact year in the return |
| Choosing PAYE and Self Assessment for the same charge | The liability can be collected twice | Confirm the selected route and final return |
Complete the Child Benefit section in Self Assessment
- 1Confirm the tax year and whether you or your partner received Child Benefit.
- 2Review HMRC’s pre-populated amount against payment records and claim dates.
- 3Amend any incorrect amount and provide the explanation requested by the return.
- 4Complete the section manually if HMRC’s information is missing or incomplete.
- 5Check the higher earner’s adjusted net income and the resulting charge before submitting.
- 6Retain the payment records, correction explanation and submitted-return confirmation.
Frequently Asked Questions
Evidence and decision checks
A reliable uk child benefit prepopulated self assessment 2026 27 review starts by fixing the tax year and the date on which the relevant event happened. Record the person's or business's status, the income or transaction category, the amount before tax, tax already withheld, and any election or claim being relied on. Do not combine a headline figure with a final liability: the result can change when another income source, a payment date, an ownership interest or a qualifying condition is added.
Keep the source documents behind every important input. Depending on the subject, that may include payslips, invoices, bank statements, contracts, provider statements, travel records, HMRC notices, payroll submissions, valuations or correspondence. Where an amount is apportioned, write down the method and retain the underlying total. If a correction is made, preserve the original figure and explain the reason, date and evidence for the replacement.
Before relying on the result, check the current official guidance for the same tax year and jurisdiction. Distinguish enacted law from a consultation, draft measure, announcement or future proposal, and record the effective date. Reconcile the final estimate to the relevant return, payroll record or HMRC account. A calculator or explanatory guide can support a decision, but it cannot replace the eligibility test or the official filing and payment process.
Evidence and decision checks
A reliable uk child benefit prepopulated self assessment 2026 27 review starts by fixing the tax year and the date on which the relevant event happened. Record the person's or business's status, the income or transaction category, the amount before tax, tax already withheld, and any election or claim being relied on. Do not combine a headline figure with a final liability: the result can change when another income source, a payment date, an ownership interest or a qualifying condition is added.
Keep the source documents behind every important input. Depending on the subject, that may include payslips, invoices, bank statements, contracts, provider statements, travel records, HMRC notices, payroll submissions, valuations or correspondence. Where an amount is apportioned, write down the method and retain the underlying total. If a correction is made, preserve the original figure and explain the reason, date and evidence for the replacement.
Before relying on the result, check the current official guidance for the same tax year and jurisdiction. Distinguish enacted law from a consultation, draft measure, announcement or future proposal, and record the effective date. Reconcile the final estimate to the relevant return, payroll record or HMRC account. A calculator or explanatory guide can support a decision, but it cannot replace the eligibility test or the official filing and payment process.
Evidence and decision checks
A reliable uk child benefit prepopulated self assessment 2026 27 review starts by fixing the tax year and the date on which the relevant event happened. Record the person's or business's status, the income or transaction category, the amount before tax, tax already withheld, and any election or claim being relied on. Do not combine a headline figure with a final liability: the result can change when another income source, a payment date, an ownership interest or a qualifying condition is added.
Keep the source documents behind every important input. Depending on the subject, that may include payslips, invoices, bank statements, contracts, provider statements, travel records, HMRC notices, payroll submissions, valuations or correspondence. Where an amount is apportioned, write down the method and retain the underlying total. If a correction is made, preserve the original figure and explain the reason, date and evidence for the replacement.
Before relying on the result, check the current official guidance for the same tax year and jurisdiction. Distinguish enacted law from a consultation, draft measure, announcement or future proposal, and record the effective date. Reconcile the final estimate to the relevant return, payroll record or HMRC account. A calculator or explanatory guide can support a decision, but it cannot replace the eligibility test or the official filing and payment process.
Why is Child Benefit already in my Self Assessment return?
Do I have to accept HMRC’s pre-populated Child Benefit figure?
What if Child Benefit is missing from my return?
Does pre-population calculate the correct HICBC automatically?
Can I pay the High Income Child Benefit Charge through PAYE?
What evidence should I keep?
Does pre-population mean HMRC knows which partner owes the charge?
Can I stop Child Benefit instead of paying the High Income Child Benefit Charge?
Read HMRC’s Agent Update 146 section on pre-populated Child Benefit, the High Income Child Benefit Charge guidance and the PAYE collection route. For rates and eligibility, use the Child Benefit guide.
Official sources
Related Guides
High Income Child Benefit Charge 2026/27 — £60k/£80k Taper & Examples
High Income Child Benefit Charge in 2026/27: the £60,000 to £80,000 taper, 1% per £200 calculation and opt-out rules.
UK Tax Calendar 2026/27 — PAYE, Self Assessment and Landlords
A practical UK tax calendar for 2026/27, covering tax-year milestones, Self Assessment, payments on account, PAYE reminders and year-end planning.
Child Benefit UK 2026/27 — Rates, Eligibility & How to Claim
Child Benefit UK 2026/27: weekly rates, who can claim, National Insurance credits, backdating, high-income charge choices and the claim process.
Review notes and assumptions
Reviewed
2026-09-20
Assumptions
- This guide reflects HMRC’s pre-population update checked on 20 September 2026 and concerns Self Assessment reporting for the 2025/26 tax year in the 2026/27 filing cycle.
- Pre-populated information is based on data HMRC holds and must be checked against the Child Benefit actually received by the claimant or their partner.
- The guide explains the reporting workflow and does not calculate the High Income Child Benefit Charge for a particular household; the higher earner’s adjusted net income and the Child Benefit amount control that calculation.