The Self Assessment deadlines that matter for OnlyFans income are 5 October to register if you are new, 31 October for a paper return, 31 January for the online return and for paying the bill plus any first payment on account, and 31 July for the second payment on account. For the 2025 to 2026 tax year that means 31 October 2026 on paper and 31 January 2027 online and for payment. Filing late starts with a £100 penalty, and paying late adds percentage penalties and interest.
Every date and penalty here comes from GOV.UK pages checked on 2 October 2026. If you have not registered yet, read our guide to when to register as self-employed first; for the wider rules on trading income, gifts and National Insurance, see our UK creator tax overview.
Calendar for the 2025 to 2026 tax year
The tax year ran from 6 April 2025 to 5 April 2026. Dates come from GOV.UK's Self Assessment deadlines page; the weekday notes are ours.
| Date | Deadline | Who it affects | Watch out for |
|---|---|---|---|
| 5 October 2026 (Monday) | Tell HMRC you need to file, by registering | First-time filers, and those registered before with no return due for 2024 to 2025 | Late registration brings a new filing date but no extra time to pay |
| 31 October 2026 (Saturday) | HMRC must receive a paper return by 11:59pm | Anyone filing on paper | GOV.UK mentions no weekend allowance for paper returns, so post it well before |
| 30 December 2026 (Wednesday) | File online by 11:59pm to have the bill collected through your tax code | Creators who also have PAYE employment | Miss it and you pay another way |
| 31 January 2027 (Sunday) | Online return, balancing payment for 2025 to 2026 and first payment on account for 2026 to 2027 | Everyone in Self Assessment | Unless you pay by Faster Payments or card, the money must reach HMRC by Friday 29 January |
| 31 July 2027 (Saturday) | The second payment on account towards 2026 to 2027 | Anyone with payments on account | Other than Faster Payments or card, payments need to arrive by Friday 30 July |
| 31 January 2028 | Last day to correct the 2025 to 2026 return online or by sending another paper return | Anyone who finds a mistake after filing | After that, changes have to be made by writing to HMRC |
Two rows need explaining. The weekend notes rely on GOV.UK's Pay your Self Assessment tax bill guide, which says that when a deadline falls on a weekend or bank holiday your payment must reach HMRC on the last working day before, unless you pay by Faster Payments or by debit or credit card. The correction row follows GOV.UK's rule that a return can be corrected within 12 months of the Self Assessment deadline, the same pattern as its own example for the 2024 to 2025 year. If you register after 5 October 2026, the deadlines page says HMRC will set a filing date 3 months from the date of its letter or email, but the tax is still due by 31 January 2027.
How payments on account work
GOV.UK's payments on account page describes them as advance payments towards your next bill, including Class 4 National Insurance, each worth half of the previous year's tax and due on 31 January and 31 July. You do not have to make them if last year's bill was under £1,000, or if more than 80% of the tax you owed was collected outside Self Assessment, for example through your tax code.
The first year is where creators get caught. If you made no payments on account the previous year, because it was your first return, the January payment is the whole of that year's bill plus the first payment on account for the next year. GOV.UK's worked example is a £3,000 bill: £4,500 due by 31 January, then £1,500 on 31 July. After that, each January brings any balancing payment for the year just finished together with the first payment on account for the year you are in.
If you expect a lower bill, for instance after a quiet year, you can ask HMRC to reduce payments on account online or with form SA303. The same page warns that if you reduce them and the bill turns out higher, you will be charged interest on the difference.
Payments on account cash planner
Fill this in from your own figures. Lines A and B come from your HMRC online account or tax calculation; nothing here should be guessed from someone else's numbers. If income swings month to month, our payout forecast worksheet helps you estimate the year before the return is done.
| Line | Enter or calculate | Source |
|---|---|---|
| A | Income Tax and Class 4 National Insurance for 2025 to 2026 | Your tax calculation once the return is prepared |
| B | Payments on account already made towards 2025 to 2026, or zero in a first year | Your Self Assessment statement |
| C | Balancing payment due 31 January 2027: A minus B | Your working |
| D | First payment on account for 2026 to 2027: half of A, unless an exception applies | GOV.UK payments on account rules |
| E | Total for 31 January 2027: C plus D | Your working |
| F | Second payment on account, due 31 July 2027: the same as D | Your working |
| G | Weekly amount to move to a tax savings pot: E divided by the weeks left before January | Your working |
Before line A is known, the deadlines page notes you can estimate your Self Assessment bill ahead of filing to budget and pay on time. You can also pay before the deadline in instalments: GOV.UK's payment guide lists weekly or monthly payments and one-off transfers towards the bill.
Penalties if you miss a date
GOV.UK's Self Assessment penalties page separates filing late from paying late, and both can apply to the same year.
| How late | Return filed late | Tax paid late |
|---|---|---|
| Once late | An initial £100 penalty | Interest is charged on what you owe |
| 30 days | No new filing penalty yet | 5% of the tax unpaid |
| 3 months | £10 a day, up to a maximum of £900 | Interest keeps running |
| 6 months | A further 5% of the tax due or £300, whichever is greater | Another 5% of the tax still unpaid |
| 12 months | Another 5% or £300, whichever is greater | A further 5% of the tax still unpaid |
Penalties must be paid within 30 days of the notice. If you think one is wrong, GOV.UK's page on disagreeing with a penalty says you usually have 30 days from the date it was issued to contact HMRC or appeal, and that HMRC will offer a review if it does not change its decision. A reasonable excuse is usually needed; the GOV.UK list includes a close bereavement, an unexpected hospital stay or a computer failure while preparing an online return, and excludes not having enough money, finding the online system too hard, or not getting a reminder.
Penalty-avoidance checklist
- File online early: GOV.UK says you can submit any time from 6 April, and filing early tells you the bill months before you pay it.
- Do not wait for perfect figures. The deadlines page says you still need to send a return if you do not know your profit for the whole year, and links to how to do that.
- Pick a payment method that arrives in time: online banking, Faster Payments, CHAPS and debit or corporate credit card are same or next day, Bacs and an existing Direct Debit take 3 working days, and a new Direct Debit takes 5.
- Remember that the Post Office is no longer a way to pay HMRC.
- If you cannot pay in full, ask HMRC about a payment plan before the deadline; GOV.UK says it checks whether a plan is affordable for you.
- Check your payments on account each January and reduce them only with a realistic estimate, since under-reducing costs interest.
- Keep records for at least 5 years after the 31 January deadline for each year, as GOV.UK requires of the self-employed.
- Correct mistakes within the 12-month window rather than waiting for HMRC to find them.
The payment-timing points come from GOV.UK's payment guide and the payment plan point from its page on what to do if you cannot pay your tax bill on time. Monthly statements make all of this easier; our OnlyFans earnings tracker template keeps the gross figures your return needs.
When Making Tax Digital changes the calendar
Some creators will soon report on a different rhythm. GOV.UK's Making Tax Digital for Income Tax guidance says sole traders whose qualifying income was over £30,000 for 2025 to 2026 will need to use it from 6 April 2027, and those over £20,000 for 2026 to 2027 from 6 April 2028. HMRC reviews each return and writes to people over the threshold, but the guidance says it is still your responsibility to check if no letter arrives. A Self Assessment return is still required for the year before you start, so the dates above keep applying until then; the MTD reporting dates themselves are set out in GOV.UK's step-by-step guidance.
Limits of this calendar
This is general information from GOV.UK pages as they read on 2 October 2026, not tax advice. It covers individuals filing their own Self Assessment, not partnerships, trusts or companies, and it does not state interest rates, which HMRC publishes separately and changes over time. Penalties can be appealed or reduced in some circumstances, so treat the table as the starting point HMRC describes rather than a forecast of any outcome.
If you are behind on several years, or a payment on account looks wrong, speak to a qualified accountant or tax adviser before the next date in the calendar. GOV.UK reminds taxpayers that the figures on a return remain your responsibility even when an agent files it.