Industry guidance
HMRC Enquiry Help for Online sellers
HMRC enquiry and disclosure guidance for eBay, Etsy, Amazon, Vinted and other online sellers covering trading status, platform reporting and VAT.
At a glance
- Online marketplaces now report seller income data directly to HMRC
- Occasional selling of personal items is usually different from taxable trading
- The trading allowance gives a modest tax-free threshold before income needs declaring
- VAT registration becomes relevant once taxable turnover crosses the registration threshold
- Internationally sourced stock brings import VAT and customs duty considerations alongside income tax
- Import documentation should be kept alongside sales records for a complete picture
Rules requiring online marketplaces to report seller income data to HMRC have significantly increased HMRC's visibility of income earned through platforms like eBay, Etsy, Amazon and Vinted. A common enquiry starting point is simply establishing whether the activity amounts to trading at all, since selling personal possessions occasionally is generally not taxable, while regular buying and reselling for profit usually is. The trading allowance provides a modest tax-free threshold, but income above it needs to be declared.
Where selling has grown from a hobby into a genuine business, questions often arise about exactly when trading began, how stock and costs have been recorded, and whether VAT registration should have been considered once turnover crossed the threshold. Sellers using multiple platforms, or selling both personally owned items and purchased-for-resale stock, should be able to separate the two clearly, since only the trading activity is generally taxable.
Once trading is established, HMRC's attention typically shifts to when the activity actually began, since backdating the start of trading incorrectly can affect which tax years are in scope and whether registration for VAT or Self Assessment was required earlier than assumed. Keeping a simple log of when regular buying-to-resell activity started, alongside evidence like initial stock purchases or a first business-related bank transaction, can make this significantly easier to demonstrate.
Sellers who source stock internationally, whether through dropshipping, importing, or buying from overseas wholesalers, need to consider import VAT and customs duties alongside their income tax position, since these costs affect genuine profit margins and may themselves be subject to separate compliance checks. Keeping import documentation alongside sales records helps present a complete and consistent picture if HMRC reviews the business.
Tax areas most relevant to online sellers
- Trading allowance and hobby-versus-trading status
- Platform data-sharing and income reporting
- VAT registration threshold monitoring
- Stock and cost of goods sold records
- Multi-platform income reconciliation
- Import VAT and customs duties on internationally sourced stock
- Dropshipping and overseas wholesale cost documentation
How to prepare
A structured, evidence-led approach from the outset tends to produce a faster and less stressful outcome than responding to each request as it comes in.
- 1
Gather sales and fee records from every platform used, not just the main one
- 2
Separate personal item sales from stock bought specifically for resale
- 3
Establish and evidence the date trading activity actually began
- 4
Track turnover against the VAT registration threshold on a rolling basis
- 5
Keep cost and stock records to support gross profit calculations
- 6
Gather import documentation for any internationally sourced stock, including VAT and duty paid
- 7
Reconcile import costs against sales records to confirm genuine profit margins
What documentation to gather
- Sales records from each platform used, including fees and net payouts
- Purchase or cost records for stock bought for resale
- Evidence distinguishing personal item sales from trading stock, if relevant
- A record of when trading activity is considered to have started
- VAT registration status and turnover monitoring records
- Import declarations and VAT/duty payment records for internationally sourced stock
- Supplier invoices from overseas wholesalers or dropshipping arrangements
Common mistakes to avoid
These are the errors we see most frequently in this sector — being aware of them in advance can help you avoid an entirely preventable dispute with HMRC.
Assuming income under the trading allowance doesn't need any record-keeping at all
Mixing personal item sales with resale stock without any separation
Not tracking turnover against the VAT threshold until after it's already been crossed
Underestimating how far back trading activity actually started
Relying solely on platform-reported figures without reconciling fees and refunds
Not keeping import VAT and duty documentation alongside sales and stock records
Understating costs by ignoring import charges when calculating genuine profit margins
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What happens next
Knowing the typical sequence of events helps you feel more in control and know roughly what to expect at each stage.
HMRC reviews platform data against your declared income
You may be asked to clarify whether activity constitutes trading or personal sales
The correct start date of trading and VAT registration position is established
HMRC calculates any additional tax due where trading income was underdeclared
The check concludes with an agreed position or a formal decision you can appeal
Import documentation is reviewed alongside sales records where internationally sourced stock is involved
Genuine profit margins are recalculated to reflect import VAT and duty costs where relevant
Frequently asked questions
The questions we're asked most often by businesses in this sector, answered in plain English.
Do I need to pay tax on selling my old belongings online?
Generally no, if you're simply selling personal possessions you no longer want, rather than buying or making items specifically to resell for profit. Regular reselling activity is more likely to count as trading.
What is the trading allowance?
It's a tax-free allowance for small amounts of trading income, letting you earn up to a set threshold from occasional trading without needing to register or declare it, though income above that threshold does need reporting.
Will HMRC know about my online selling income?
Online marketplaces are now required to report seller transaction data to HMRC, which means undeclared trading income is considerably easier for HMRC to identify than in the past.
Do I need to register as self-employed to sell online?
If your activity amounts to regular trading rather than occasional personal sales, yes — registering promptly once trading begins avoids penalties for late notification.
What if I sell across several different platforms?
All platforms need to be included when calculating total trading income and monitoring the VAT threshold, since HMRC looks at your overall trading activity, not each platform in isolation.
Can I deduct platform fees from my income?
Yes, platform fees and other costs genuinely incurred in making the sale are generally allowable business expenses that reduce your taxable profit.
Do I need to pay import VAT on stock I buy from overseas?
Generally yes, and this needs factoring into your cost calculations and kept as part of your records, since it affects your true profit margin on those items.
How does dropshipping affect my tax position?
You're generally still trading and need to declare the income, though your records need to clearly show the relationship between what customers paid and what you paid your supplier.
Can import costs be deducted as a business expense?
Yes, genuine import VAT, duty and shipping costs incurred in buying stock for resale are generally allowable business expenses that reduce your taxable profit.
What records should I keep for imported stock?
Import declarations, VAT and duty payment evidence, and supplier invoices should all be retained alongside your regular sales records for a complete picture.
Does it matter if I use a personal or business bank account for online sales?
Using a personal account doesn't exempt trading income from tax, but a dedicated business account makes reconciling income and expenses considerably more straightforward if HMRC ever asks questions.
What if a platform's reported figures don't match my own records?
It's worth reconciling the two promptly, since discrepancies between platform data and declared income are precisely the kind of gap HMRC's checks are designed to identify.
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