HMRC rules for online sellers, explained

The rules around selling online have evolved, and the headlines can sound alarming. In reality, most casual sellers have nothing to worry about, and the genuinely important rules are straightforward once broken down. This page summarises the current HMRC rules for online sellers in plain English. Our checker then applies them to your situation in about a minute.

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Rule 1: Are you trading?

HMRC’s starting point is whether your selling amounts to trading. They apply the ‘badges of trade’ — looking at whether you buy to resell, sell systematically, seek a profit, or sell things you made. Selling your own unwanted possessions to declutter is usually private and not trading. This distinction underpins everything else.

Rule 2: the £1,000 trading allowance

If you are trading, the first £1,000 of gross income each tax year is tax-free. Below that you usually need not report anything; above it you generally register for Self Assessment and declare your profit. You choose between the flat allowance and actual expenses, but not both.

Rule 3: platform reporting

Under the new reporting regime, digital marketplaces must report sellers who reach around £1,700 of sales or 30 transactions in a calendar year. This is data-sharing to improve compliance — being reported does not mean you owe tax. Your liability still depends on trading status and allowances.

Rule 4: valuable personal possessions

Separately, selling a single personal possession for more than £6,000 can raise Capital Gains Tax considerations, even where the sale is not trading. This is a different tax from income tax on trading profits, so it is worth knowing about if you sell higher-value items.

How accurate are these rules?

The rules summarised here reflect HMRC guidance as verified on 2026-07-01. Tax rules and thresholds can change, so always confirm the current position on gov.uk or with a qualified accountant before filing. Our checker states the ‘last verified’ date alongside its results so you know how current the figures are.

Frequently asked questions

Do HMRC rules mean all online selling is taxed?
No. Selling your own unwanted belongings is usually a private sale and not taxable. Tax generally only applies if you are trading and your income exceeds the £1,000 allowance.
What are the platform-reporting thresholds?
Marketplaces must report sellers who reach roughly £1,700 of sales or 30 transactions in a calendar year. This is reporting for compliance, not an automatic tax bill.
What is the trading allowance?
A tax-free allowance covering the first £1,000 of gross trading income each tax year. Below it you usually need not report; above it you generally register for Self Assessment.
How do I know if I am ‘trading’?
HMRC uses the ‘badges of trade’ — intent to profit, frequency, nature of goods, and whether items were bought to resell. Our checker walks through these with you.
Are these rules up to date?
They reflect HMRC guidance as last verified on the date shown in our tool. Tax rules can change, so confirm the current position on gov.uk before filing.

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