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HMRC Self Assessment Deadlines

Track UK Self Assessment registration, paper and online return deadlines, PAYE coding date, tax payment date, and payments on account.

Published: May 18, 2026Updated: May 19, 2026

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HMRC Self Assessment Has Four Main Deadline Types

UK Self Assessment planning has registration, filing, payment, and payments-on-account dates. The online return and main payment date are commonly 31 January after the tax year, but other dates can matter first.

This guide is UK-specific and does not duplicate the global taxes due article.

Estimate PAYE income tax

Common HMRC Self Assessment Dates

Date	What it is	Planning note
5 October	Register for Self Assessment if newly required.	Do not wait until January if you are new to Self Assessment.
31 October	Paper tax return deadline.	Online filing has a later standard deadline.
30 December	Deadline to request eligible tax collection through PAYE code.	Only works if HMRC conditions are met.
31 January	Online return, balancing payment, and first payment on account.	Main deadline for most online filers.
31 July	Second payment on account.	Review if current-year income is lower before reducing payments.

Payments on Account Are Not a Second Tax Return

Payments on account are advance payments toward the next tax year, usually based on the previous year. They can make the 31 January bill feel larger because the balancing payment and first advance payment may land together.

If your income falls, you can ask HMRC to reduce payments on account, but underestimating can create interest.

Self Assessment Records Checklist

Employment income and P60/P45 details.
Self-employment sales, expenses, and bank records.
Rental income, mortgage interest, repairs, and property expenses.
Dividend, savings interest, capital gains, and pension records.
Student loan, Gift Aid, pension contributions, and child benefit charge details.
Payments on account and previous Self Assessment payment records.

Official Video Check

GOV.UK points taxpayers to HMRC Self Assessment support videos, but no current concise official video was found that cleanly covers the full deadline map for this guide. This article therefore uses GOV.UK written deadline and payment sources.

Self Assessment Scenarios That Change the Deadline Work

HMRC Self Assessment planning should separate four jobs: registering when you are new to Self Assessment, filing the tax return, paying the balancing payment, and making payments on account when they apply. A taxpayer can be on time for one job and still miss another. That is why a deadline guide should not only list dates; it should show which task each date controls.

First-time filers need extra lead time because registration, Government Gateway access, and activation codes can delay online filing. Taxpayers who want tax collected through a PAYE code may need to file earlier than the final online deadline. Self-employed taxpayers, landlords, partners, high-income child benefit cases, and people with untaxed investment income should check whether payments on account will create a second payment date later in the year.

Register early if this is the first year Self Assessment applies.
Decide whether a paper return, online return, or agent route controls the filing date.
Separate the 31 January balancing payment from the return-submission task.
Check whether payments on account are due for the current tax year.
Keep CIS, P60, P45, P11D, rental, pension, bank interest, dividend, and expense records together.
Review HMRC notices because penalties and interest can apply even when only the payment is late.

Frequently Asked Questions

The standard online Self Assessment deadline is 31 January after the end of the tax year, unless HMRC gives a different deadline.

HMRC generally uses 31 January for the balancing payment and first payment on account, and 31 July for the second payment on account.

In some cases, a smaller Self Assessment bill can be collected through a PAYE tax code if the return is submitted by the relevant 30 December deadline and HMRC rules are met.

New Self Assessment filers usually need to register by 5 October after the tax year in which they became liable, unless HMRC gives a different deadline.

Paper tax returns usually have an earlier 31 October deadline, while online returns usually have a 31 January deadline after the tax year.

A payment on account is an advance payment toward the next Self Assessment bill. HMRC generally splits it into two payments due 31 January and 31 July.

HMRC rules can remove payments on account when the prior bill is below the threshold or enough tax was already collected outside Self Assessment.

A Unique Taxpayer Reference identifies a Self Assessment record. First-time filers should allow time to receive and activate access before filing online.

Sometimes, but the return usually needs to be filed earlier than the final online deadline and the amount must fit HMRC collection rules.

Late filing penalties can still apply even if no tax is due. File or contact HMRC as soon as possible if a deadline was missed.

Yes, amendments are usually allowed within HMRC time limits. The correction can change tax, payments on account, interest, and penalties.

An agent can help file, but the legal deadline still applies unless HMRC has issued a different deadline for the taxpayer or return type.