If you sell the odd item on eBay, Vinted or Facebook Marketplace, you’ve probably wondered when it becomes “taxable”. There’s been a lot of noise about platform reporting and a so-called “30-item rule”, which has left many people unsure about what to do. This guide sets out the HMRC rules for casual online sellers in plain English, including what counts as trading, how the £1,000 trading allowance works, what platforms share with HMRC, and when you need to register for self assessment. We also touch on record-keeping and Making Tax Digital so you can plan ahead with confidence.
A quick reality check first. If you’re simply clearing out personal belongings at a loss, you’re unlikely to have anything to report. HMRC is interested when you’re trading – for example buying items to resell, or selling regularly with a profit motive. In the same breath, HMRC isn’t introducing a new tax on side hustles. The tax rules already exist. What’s changed is the flow of data: from 2024, digital platforms must share seller information with HMRC under international reporting standards. That helps HMRC cross-check returns, but it doesn’t change the basic HMRC rules for casual online sellers.
Why does this matter now? Online selling keeps rising as a share of retail. In July 2025, online sales made up around 26-27% of retail activity in Great Britain, showing how normal these routes have become for households and small businesses alike (ONS, 2025). If you’re turning a hobby into regular income, it pays to understand the HMRC rules for casual online sellers so you can keep things simple, set aside the right money for tax, and avoid avoidable penalties.
What counts as trading, not just decluttering
HMRC looks at the overall picture to decide if you’re trading. There isn’t a single bright line, but patterns matter. Ask yourself:
- Frequency: Are you selling regularly, not just once in a while?
- Purpose: Are you buying items specifically to resell at a profit?
- Organisation: Do you keep stock, list items methodically, use branding or paid adverts?
If most answers lean “yes”, you’re likely trading. That’s the point where the HMRC rules for casual online sellers start to apply and you should look at the trading allowance and Self Assessment.
How the £1,000 trading allowance works
- Trading allowance: Up to £1,000 tax-free gross income. You can earn up to £1,000 in total gross trading or casual income in a tax year without needing to report it to HMRC. Go over £1,000 and you must tell HMRC and either claim the allowance or deduct actual expenses.
- One allowance, total activity: The £1,000 covers all your trading and casual income combined. You can’t have multiple £1,000 allowances across different platforms.
- Record-keeping still helps: Even under £1,000, basic records make life easier if HMRC ever asks questions or you scale up.
Check the official guidance on whether you need to tell HMRC about income from online platforms (HMRC, 2025).
Do platforms report your sales to HMRC?
From 1 January 2024, UK rules require many digital platforms to collect and report information about sellers’ income to HMRC, aligned with the OECD’s model reporting rules. That includes marketplace apps and websites for goods, short-term property lets and certain services. Platforms also give sellers a copy of what’s reported so you see what HMRC sees. The reporting is based on calendar years and sits alongside, not instead of, your tax-year obligations (HMRC, 2024).
There’s been chat about a “30-item or about €2,000” threshold. That’s part of how platforms decide who must be reported under international rules, not a UK tax-free amount. In short:
- Platform reporting is not a tax: It doesn’t mean you automatically owe tax.
- Tax still follows UK rules: If you’re trading and your gross income exceeds £1,000, you must tell HMRC, regardless of whether the platform reported you.
When you must register for Self Assessment
Once your gross trading income is over £1,000 in the tax year, or you’re otherwise required to file, you should register for self assessment if you haven’t before. Key points for 2025/26:
- Registration deadline: Tell HMRC by 5 October following the end of the tax year if you need to complete a tax return and haven’t filed one before.
- Filing deadlines: Paper returns are due 31 October. Online returns and any tax due are due by 31 January following the end of the tax year. If you register late, HMRC usually sets a filing deadline three months from their notice – the 31 January payment deadline still applies.
- Payments on account: If your last bill is over £1,000 and not mostly taxed at source, you may need to make payments on account in January and July. Budgeting early avoids surprises.
These timeframes sit alongside the HMRC rules for casual online sellers and are worth diarising if your sales are taking off.
Expenses, cash basis and simple records
Since April 2024, the cash basis is the default for most sole traders and partnerships without corporate members. You record income when it hits your account and expenses when paid. That keeps bookkeeping straightforward and aligns well with platform payouts. Keep:
- Sales evidence: Platform statements, order history, payout reports.
- Expenses: Postage, packaging, selling fees, small tools, mileage where applicable.
- Inventory: What you’ve bought to resell, with dates and costs.
You can either deduct actual expenses or, if it’s simpler and beneficial, claim the £1,000 trading allowance instead. Run the numbers both ways. If fees and costs are well over £1,000, actual expenses usually win.
Making Tax Digital: What’s coming next
Making Tax Digital for Income Tax (MTD ITSA) becomes mandatory in phases from 6 April 2026 for self-employed individuals and landlords with qualifying income over set thresholds. If your online selling evolves into a steady trade, expect to keep digital records and send quarterly updates via compatible software. It’s sensible to adopt simple software early, even if you’re not yet mandated, so the habit is in place before the rules apply.
This does not change the HMRC rules for casual online sellers, but it will affect how and when you send information if your activity grows.
Practical scenarios: Do I need to tell HMRC?
- Occasional decluttering: You sell a few unwanted items at a loss to make space.
- Likely position: Not trading, no Self Assessment needed. Keep screenshots in case HMRC asks later.
- Hobby seller edging into trade: You sell personal items, then start buying bundles to resell. You take regular payouts and your gross income tops £1,000.
- Likely position: You are trading. Register for self assessment, decide between the trading allowance or actual expenses, and keep proper records.
- Regular reseller: You source stock weekly, list methodically and reinvest profits.
- Likely position: Trading beyond doubt. You must follow the HMRC rules for casual online sellers, file on time, and consider MTD preparations.
How we can help
We work with owner-managed businesses across ecommerce, hospitality, construction, manufacturing and startups. If your sales are growing, we’ll set you up with clean records, platform integrations and a tax plan that fits your goals. For casual sellers, a short call can clarify whether you’re inside the HMRC rules for casual online sellers or safely outside them.
Key takeaways for casual online sellers
- Trading allowance: Up to £1,000 gross income. Over that, you must tell HMRC and submit a return, or ensure your situation is otherwise covered.
- Platform reporting: Platforms share seller data with HMRC – that’s information flow, not a new tax. Keep your own records to match your statements.
- Deadlines: Register by 5 October if new to Self Assessment, file by 31 October on paper or 31 January online, and pay by 31 January.
- Best practice: Use the default cash basis, store platform statements, and review whether the allowance or actual expenses gives the better result.
- Looking ahead: MTD for Income Tax arrives from April 2026 for many traders – mild changes now save hassle later.
If you’d like a quick review of your selling activity, we offer a short diagnostic to confirm whether the HMRC rules for casual online sellers apply to you and what to do next. Talk to us about the HMRC rules for casual online sellers and get clear, practical steps for the year ahead.
