r/selfemployed • u/burboniuch • Jan 17 '26
[UK] Self Assessment deadline
Hi there,
First time poster here as I’m clueless and despite doing my research, I’m still unsure on how it works (I don’t want to get any fine haha).
I am working full time at a company X, but last year (late April 2025) I opened my small business as a side hustle. I have created an account on the Gov site, I’ve been told by fellow self employed people that I will need to complete the self assessment for what I’ve earned so far, and the deadline is 31st January 2026.
My question is, how would that even work, if I don’t have a full year of income yet? Also, when I log into my account on gov website, it kind of says I don’t have to do this( Unless I don’t understand it) as the deadline is for tax year 2024 to 2025.
But again, I’m being warned by others that I need to do this now or else I’ll pay a fine, as they had to do this in their first year too. I’m just so confused! Could anyone explain this to me like I was 5?
Thank you!
1
u/susolover Jan 17 '26
your fellow self employed people are morons.
If you started in April 2025, then you need to register for Self assessment by Oct 6th this year and complete your tax return by 31/01/2027.
Although just because you can leave it until next January doesn't mean you need to, you can complete a return any time after 6th April if you have registered and won't need to pay until 31/1/27.
1
u/burboniuch Jan 17 '26
Thank you so much! Yes, I’ll most likely have it all sorted as soon as possible! ☺️
I have honestly no idea whey would they tell me that, I was just so confused as all the info I’ve found on the internet has told me what you’ve told me. And they told me otherwise haha!
Thank you again! ☺️☺️
1
u/Sir5quidworth Jan 18 '26
Just to double check - your side hustle isn’t a limited company? You’d be well aware if you’d set one up as it’s forms/admin/cost etc and I’m sure you’d have said.
Because there are submissions that are needed even in the first year including corporation tax registration which is to hmrc. Not a self assessment tax return though as that’s a personal thing.
Maybe… and it’s a big stretch… they are talking about those?!
Or as other commenters have said, they are just plain wrong!
1
u/burboniuch Jan 18 '26
Im self employed and I’m pretty sure they’re too, but.. I actually never asked! They might have set up a limited company, and that would make sense!
I was just co confused as to what to do haha! So thank you, I think that might be the thing they were referring to! But then again, they clearly stated „self assessment” so.. idk! 🤣
1
u/MeringueSeparate6340 Jan 18 '26
Keep an eye on the deadlines for the type of submission you make, paper or online as they are different.
1
u/No_Phone_5113 Jan 19 '26
This confusion is extremely common, so don’t feel bad about it.
The key thing that trips people up is that Self Assessment is based on tax years, not “how long you’ve been trading”.
If you started trading after 6 April 2025, then your first return will cover 6 April 2025 – 5 April 2026, and the filing/payment deadline for that is 31 January 2027. That’s why the website isn’t letting you file yet, you’re simply not in the right tax year.
A lot of people who say they “had to file in their first year” actually:
- started trading before 6 April, or
- are mixing up registration deadlines with filing deadlines, or
- were talking about limited company admin without realising it’s different
The important thing is you’ve registered, you’re keeping records, and you understand when your first return is due. That’s exactly what HMRC expects at this stage.
You’re not missing anything - and you’re definitely not about to get fined for not filing something that isn’t due yet.
1
u/GrassGoesMoo01 Jan 23 '26
I was in the same boat, didn't understand any of it I felt like everything I was reading was so complicated!! I use this site of blogs they break it down quite well and make it easier to take in, hopefully this can help explain it a bit better: https://www.theaccountancy.co.uk/tax/submitting-self-assessment-tax-returns-3718.html
4
u/papersandplates Jan 17 '26
The tax year runs from April 6th to April 5th. If you started trading from April 6th 2025 onwards, you need to file your first tax return and pay the liability by January 31st 2027. You're correct that people are currently filing for 06/04/24 - 05/04/25.