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January Tax Deadline Checklist for Online Sellers
Sold on Vinted, eBay, Depop or elsewhere between 6 April 2025 and 5 April 2026, and need to send a Self Assessment tax return? Your online return for that tax year is due by 11:59pm on 31 January 2027, and so is any tax you owe. Work through this list in good time.
Checked 31 October 2026 against GOV.UK · General information, not tax advice
Key dates for the 2025/26 tax year
| Date | What it means |
|---|---|
| 6 April 2025 to 5 April 2026 | The tax year this return covers. |
| 5 October 2026 | Deadline to register for Self Assessment if you have not sent a return before, or did not need to send one for 2024/25. Missed it? Register now (see step 2). |
| 31 October 2026 | Paper returns were due by 11:59pm. If you have not sent one, the online deadline below applies. |
| 30 December 2026 | File online by 11:59pm if you want any tax owed collected through your PAYE tax code (only if you owe less than £3,000 and already pay tax through PAYE). |
| 31 January 2027 (a Sunday) | Online return due by 11:59pm. Pay what you owe for 2025/26, plus your first payment on account for 2026/27 if you have to make one. |
| 31 July 2027 | Second payment on account due, if you have to make them. |
The checklist
1. Check whether you need to file at all
- Selling your own unwanted things is unlikely to be taxed (Capital Gains Tax can apply to a single item sold for more than £6,000). Buying things to resell, or making things to sell, is likely to be trading. Am I trading? explains the difference.
- If your trading income (before expenses) was over £1,000 in 2025/26, you need to register for Self Assessment and send a return. Not sure? Use HMRC's free tool: Check if you need to tell HMRC about additional income.
- A platform report is not a tax bill. Platforms report sellers with 30 or more sales, or about £1,700 (€2,000) or more, in a calendar year. Being reported does not automatically mean you owe tax. See eBay's HMRC reporting threshold and Vinted tax: do you need to pay?.
- The trading allowance rise to £3,000, announced at Budget 2026, starts on 6 April 2027 if it becomes law (GOV.UK: Budget 2026 overview, section 1.5). It does not change your 2025/26 return.
2. Get registered and find your details
- Not registered yet? Register for Self Assessment now. Registering after 5 October 2026 can mean a penalty, and you may need to reactivate an old account rather than start a new one.
- Find your 10-digit Unique Taxpayer Reference (UTR). It usually arrives by post about 15 days after you register, and you can also find it in your HMRC personal tax account or the HMRC app.
- Check you can sign in to file online. You will need your sign-in details and UTR, and you may need to prove your identity. You can save your return and come back to it.
- If you register after 5 October 2026, HMRC will give you a filing deadline 3 months from the date of its letter, but the tax is still due by 31 January 2027.
3. Gather your records for 6 April 2025 to 5 April 2026
- All your sales and income from each platform. Your platform sales history or payout reports are a good starting point.
- Any report a platform sent you. Platforms must give you a copy of what they send HMRC. Their reports cover the calendar year (January to December), so you still need to work out your figures for the tax year (6 April to 5 April).
- All your business expenses, with proof such as receipts for stock, bank statements and invoices. For resellers that typically includes the stock you bought to sell and postage. See allowable expenses for resellers.
- Records of any other income you need to include, such as pay from a job.
4. Choose: trading allowance or expenses
- You can deduct the £1,000 trading allowance or your actual allowable expenses, not both. If you use the allowance you cannot claim expenses.
- Compare the two before you file. Trading allowance vs expenses walks through it. You still need to keep records even if you use the allowance.
5. Work out roughly what you will owe, including payments on account
- Payments on account are advance payments towards next year's bill. Each one is usually half of last year's tax, due on 31 January and 31 July.
- You do not have to make them if the tax you owed last year was less than £1,000, or if last year you paid more than 80% of your tax outside Self Assessment, for example through your tax code.
- First-year surprise: GOV.UK's example is a £3,000 bill for the year, which means paying £4,500 by 31 January (the £3,000 bill plus a £1,500 first payment on account), then £1,500 by 31 July. See payments on account for side hustles.
- If you expect next year's profit to be lower, you can ask HMRC to reduce your payments on account, online or with form SA303. If you reduce them too far, you pay interest on the difference.
- Want a rough number? Try our reseller tax estimate.
6. File your return online
- Deadline: 11:59pm on 31 January 2027. Do not leave it to the last day.
- Aim for 30 December 2026 if you owe less than £3,000, already pay tax through PAYE and want it collected through your tax code over the following 12 months.
- Step by step: the 31 January 2027 deadline for online sellers and how to fill in Self Assessment as a reseller.
7. Pay on time
- Same or next day: through your online bank account, Faster Payments, CHAPS, or debit or corporate credit card online. 3 working days: Bacs or an existing Direct Debit. 5 working days: a new Direct Debit. You can also pay through the HMRC app. You can no longer pay at the Post Office.
- 31 January 2027 is a Sunday, but the deadline stays 11:59pm on 31 January 2027. GOV.UK says that when a deadline falls on a weekend, your payment must reach HMRC by the last working day before it (Friday 29 January 2027), unless you pay by Faster Payments or by debit or corporate credit card. Bacs and Direct Debit take 3 to 5 working days, so allow for that.
- Cannot pay in full? You may be able to set up a payment plan with HMRC.
8. Keep your records
- Keep your records for at least 5 years after the 31 January submission deadline. For 2025/26 that means until at least the end of January 2032.
If you miss the deadline
- Late filing: an initial £100 penalty. After 3 months, £10 a day, up to £900. After 6 months, a further 5% of the tax due or £300, whichever is greater. After 12 months, another 5% or £300.
- Late payment: 5% of the unpaid tax at 30 days, 6 months and 12 months, plus interest. Late payment interest is the Bank of England base rate plus 4%. GOV.UK listed it as 7.75% (from 9 January 2026) when we checked on 31 October 2026.
- Registered late: if you registered after 5 October 2026 and have not paid all your tax by 31 January 2027, you may get a penalty for not telling HMRC on time.
- Reasonable excuse: you can appeal a penalty if you had a reasonable excuse.
Quick answers
When is the Self Assessment deadline for the 2025/26 tax year?
Online returns for the tax year 6 April 2025 to 5 April 2026 are due by 11:59pm on 31 January 2027, and any tax owed must be paid by then too. Paper returns were due by 31 October 2026.
Do I need to file if Vinted or eBay reported me to HMRC?
Not automatically. Being reported does not mean you owe tax. You need to file if, for example, your trading income was over £1,000 in the tax year. Selling your own unwanted things is unlikely to be taxed.
Why might I owe more than my tax bill in January?
If you have to make payments on account, your first one for next year (usually half of this year's bill) is due on 31 January as well. In GOV.UK's example, a £3,000 bill means paying £4,500 by 31 January.
What if I cannot pay in full by 31 January?
You may be able to set up a payment plan with HMRC to pay in instalments. GOV.UK explains the options on its page about not being able to pay your tax bill on time.
Sources
- GOV.UK: Self Assessment tax returns, deadlines
- GOV.UK: Register for Self Assessment
- GOV.UK: Find your UTR number
- GOV.UK: Sign in and file your Self Assessment tax return
- GOV.UK: Tax-free allowances on property and trading income
- GOV.UK: Check if you need to tell HMRC about your income from online platforms
- GOV.UK: Selling goods or services on a digital platform
- GOV.UK: Check if you need to tell HMRC about additional income
- GOV.UK: Budget 2026 overview of tax legislation and rates, section 1.5
- GOV.UK: Business records if you're self-employed, what records to keep
- GOV.UK: How long to keep your records
- GOV.UK: Expenses if you're self-employed
- GOV.UK: Understand your Self Assessment tax bill, payments on account
- GOV.UK: Pay your Self Assessment tax bill
- GOV.UK: Pay your Self Assessment through your tax code
- GOV.UK: If you cannot pay your tax bill on time
- GOV.UK: Self Assessment tax returns, penalties
- GOV.UK: HMRC interest rates for late and early payments
More guides for UK online sellers
- Do You Pay Tax on Vinted? UK Rules & HMRC Limits 2026 – Own clothes vs reselling, the £1,000 allowance and the 30-sale reporting rule, in plain English.
- Vinted HMRC Form & NI Number Request: What to Do – Why Vinted is asking for your National Insurance number, the end-of-year deadline, and why it doesn't mean you owe tax.
- Vinted Tax Calculator UK: Free HMRC Limit Checker – Check your sales against the 30-sale / ~£1,700 reporting rule and the trading allowance, with a 2026/27 or 2027/28 tax-year switch. It checks limits, not your tax bill.
- eBay HMRC Reporting Threshold 2026: £1,707 or 30 Sales – What eBay counts towards £1,707, what it reports, and why a report isn't a tax bill.
- Got an HMRC Letter About Vinted or eBay Sales? What to Do – A calm step-by-step: check it's genuine, work out if you were trading, and reply on time.
- Free Vinted & eBay Profit Tracker Spreadsheet (UK) – A free download with tax-year tabs, profit per item and a check against the HMRC limits.
- Trading Allowance vs Expenses: Which Should Resellers Use? – The £1,000 allowance or your real costs? Why resellers who track stock costs often come out ahead with expenses.
- Do Resellers Need to Register for Self Assessment? – When reselling counts as trading, the £1,000 rule, and the 5 October and 31 January deadlines.
- Depop HMRC Reporting: Do You Pay Tax on Depop Sales? – What Depop reports, what it asks you for, and Depop's own example of being reported but owing no tax.
- Etsy UK Tax: HMRC Reporting Rules for Sellers 2026 – When Etsy reports you to HMRC, and why things you make to sell usually count as trading.
- Trading Allowance Rises to £3,000: What Budget 2026 Changed – The trading allowance is due to rise from £1,000 to £3,000 from 6 April 2027, subject to Finance Bill. When it starts, who it helps, and why £1,000 still applies until then.
- Why Is eBay Asking for My National Insurance Number? – Why eBay wants your NI number, what happens if you don't give it, and why giving it doesn't mean you owe tax.
- Selling Personal Items on eBay: Do You Pay Tax? (UK) – Clear-outs vs trading, the £6,000 Capital Gains Tax rule for valuable items, and why eBay may still report you.
- Facebook Marketplace & HMRC: Do They Report You? – What we could and couldn't confirm about Facebook Marketplace reporting, what Gumtree says, and why the tax rules are the same either way.
- Am I Trading? HMRC's Badges of Trade for Resellers – HMRC's nine badges of trade with Vinted and eBay examples, plus car boot sales: when selling becomes trading.
- Vinted Pro vs Personal Account: Does It Change Tax? – What Vinted says about Pro and standard accounts, what HMRC actually looks at, and why switching account type isn't what decides tax.
- Side Hustle Tax Calculator UK: How Much Tax Will I Pay? – A rough estimate of the extra Income Tax and Class 4 National Insurance on your reselling profit, comparing the trading allowance with your real costs. England, Wales and NI.
- Telling HMRC About Past Online Sales: Disclosure Guide – Realised you should have declared past reselling income? The routes GOV.UK describes, step by step, and how far back it goes.
- MTD for Resellers: Do eBay & Vinted Sellers Need It? – Most sellers won't need Making Tax Digital for Income Tax. The £50,000, £30,000 and £20,000 thresholds, and why they count sales, not profit.
- Whatnot UK Tax: Do Sellers Pay Tax and Does It Tell HMRC? – How Whatnot reports UK sellers to HMRC via Ireland, when live-selling income is taxable, Whatnot's fees as expenses, and the £90,000 VAT line.
- TikTok Shop UK Tax: When Sellers Pay and What HMRC Sees – TikTok Shop's 30 orders or €2,000 reporting rule, where to find your MRDP report, and why being reported isn't the same as owing tax.
- Self Assessment Deadline 2027: A Guide for Vinted Sellers – Your 2025 to 2026 return and tax are due online by 31 January 2027. Which sales it covers, the 30 December tax-code option and how to pay.
- Payments on Account Explained for Side Hustles (UK) – Why a first January tax bill can be 1.5 times what you expected, when you don't have to make payments on account, and how to reduce them.
- Reseller Expenses UK: Stock, Postage, Fees and Mileage – What resellers can claim on GOV.UK's lists: stock, postage, mileage at flat rates, use of home, and what you can't claim.
This is general information, not tax advice. Whether you owe tax depends on your circumstances. Check GOV.UK or speak to an accountant about your own situation. SideLedger is not affiliated with HMRC, Vinted, eBay or Depop.