Started freelancing this year? You have to tell HMRC by 5 October

There is one freelance deadline nobody talks about, and it is the one that catches people in their first year. Not the January tax return. The one before it: telling HMRC you exist.

If you started working for yourself at any point in the 2025/26 tax year, that is between 6 April 2025 and 5 April 2026, your deadline to register for self assessment is 5 October 2026.

Does this actually apply to you?

Work through these three questions honestly.

1. Did you earn more than £1,000 from self-employment in 2025/26? That is £1,000 gross, so the total your clients paid you, before you take off your laptop, your software, or anything else. If you earned £1,000 or less, the trading allowance covers you and you generally do not need to register or report it at all. If you went a penny over, you do.

2. Do you have a job as well? Then you still need to register. Your employer handles the tax on your salary through PAYE, but nobody is doing that for your freelance income. Selling illustrations at the weekend, taking on two client projects a year, running a side thing on Etsy: all of it counts, and HMRC treats it exactly the same as full-time freelancing.

3. Do you already file a tax return? Perhaps for rental income, or because you earn over £100,000, or because you have untaxed savings. You do not start from scratch. You add self-employment to the return you already file, which is a shorter form, but the same 5 October deadline applies to the new source of income.

What "started freelancing" actually means

People get this wrong and it changes their deadline by a full year.

Your start date is when you began trading, not when the first payment landed. If you took on your first paid client project in February 2026 but they paid you in May 2026, you started trading in the 2025/26 tax year. Your deadline is 5 October 2026, even though the money arrived in the next tax year.

Setting up an Instagram page, buying a domain, or telling friends you are available for work does not start the clock on its own. Offering your services to a real client for money does. If you are genuinely unsure, use the date of your first piece of paid work.

How to register

It is a form on GOV.UK called Register for Self Assessment, and it takes about ten minutes if you have your details to hand. You will need:

• Your National Insurance number
• Your date of birth and home address
• The date you started trading
• What your business actually does, in plain words, "graphic design" or "photography" is fine
• Your business name, if you use one, otherwise your own name

Then two things arrive, and neither is instant. First your Unique Taxpayer Reference, the ten-digit UTR you will need for every tax thing you ever do. HMRC posts it, usually within about two weeks. Then a separate activation code for your online account, also by post. If you are living abroad or your post is slow, that is the bit that bites.

This is why 5 October is a soft deadline in practice and a hard one on paper. Register on 4 October and you have met the rule, but you may still be waiting on paperwork in late October with a January filing date coming at you. Do it now instead. Nothing bad happens by being early.

What registering also protects

Registering is not only about the tax bill. It is what puts your self-employment on your National Insurance record, which is what builds your entitlement to the state pension and some benefits. Since April 2024, self-employed people with profits above the small profits threshold get that credit without paying Class 2 National Insurance separately. You still have to be registered for it to count. Trade for two years off the books and those are two years missing from your record.

Class 4 National Insurance is the one you do pay, on profits above the personal allowance of £12,570, and it comes out of the same self assessment calculation as your income tax. You do not need to do anything extra for it.

What happens if you miss 5 October

You do not get an instant fine the way you do for a late tax return. What you get is a failure to notify penalty, and it is worked out as a percentage of the tax you should have paid. No tax owed, no penalty. A big year, a big penalty.

How big depends on two things: whether HMRC thinks you did it on purpose, and who spoke first. If it was not deliberate, you come forward yourself before HMRC contacts you, and you put it right within 12 months of the tax being due, the penalty can be reduced to nothing. If you wait until HMRC gets in touch, it climbs, and it climbs a lot further if they decide you were hiding.

The practical version: if you have already missed a deadline, registering today is always cheaper than registering when you are asked to.

Then what? Your first return

Registering does not file anything. It opens the door. For the 2025/26 tax year, your return is due:

• 31 October 2026 if you file on paper
• 31 January 2027 if you file online, which is what almost everyone does

The tax itself is due on 31 January 2027 too. And here is the one that ruins first-year freelancers: if your bill comes to more than £1,000, HMRC also asks for a payment on account, which is half of that bill again, on the same day. Then another half on 31 July. You are effectively paying one and a half years of tax in your first January. It is not an extra charge, it is next year's tax paid early, but nobody warns you and it is brutal if you have spent the money.

Put a percentage of every payment aside from the day you register. Most freelancers land somewhere around 25 to 30% once income tax and National Insurance are counted, but check your own numbers rather than trusting a rule of thumb.

Does Making Tax Digital apply to you yet?

Probably not in your first year. Making Tax Digital for Income Tax started in April 2026 for self-employed people with qualifying income over £50,000, and HMRC works out who is in scope from the last tax return you filed. If you have never filed one, there is nothing for them to look at yet, so you will not be pulled in immediately.

It will reach you eventually. The threshold drops to £30,000 from April 2027 and lower after that. Keeping your invoices and expenses in a digital record now means the switch is a setting, not a rescue mission.

The bottom line

If you earned more than £1,000 freelancing between April 2025 and April 2026, put ten minutes aside this week and register. It is free, it is quick, and it is the one deadline where being early costs you nothing and being late is priced as a share of everything you earned.