Mystery Shopping Income and Tax: The £1,000 Trading Allowance in 2026/27
Mystery shopping fees, reimbursed purchases and expenses are treated differently by HMRC. How the £1,000 trading allowance applies to mystery shopper income in 2026/27.
Quick answer
Mystery shopping pays in two different ways that HMRC treats differently: a fee for doing the assignment (taxable trading income) and reimbursement for a required purchase you then keep (generally not additional income, since it just covers a cost). Most occasional mystery shoppers stay comfortably under the £1,000 trading allowance on the fee element and have nothing to report.
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Self-employed tax calculatorFees vs reimbursement
A typical assignment might pay a £15 fee plus reimburse a £20 meal you're required to order and then keep the receipt for. The £15 fee is trading income, counted towards the £1,000 threshold; the £20 reimbursement simply covers what you spent and isn't extra income on top. Keep records that separate the two, since only the fee portion determines whether you're above or below the trading allowance threshold.
The £1,000 threshold
Add up gross fees (not reimbursements) across a tax year. If the total is £1,000 or less, the trading allowance means it's tax-free and generally there's no need to register for Self Assessment purely for this activity. Cross £1,000, and you must register and declare the income, choosing between the flat £1,000 deduction or actual expenses.
self-employed-tax-ukWhat can be claimed once registered
Once above the threshold and filing Self Assessment, allowable expenses can include mileage to assignments (45p per mile for the first 10,000 business miles, 25p after), any equipment specifically bought for reporting (like a mystery-shopping-specific camera), and platform membership fees where these apply.
Platform reporting
Many mystery shopping schemes now run through digital platforms, which under UK rules aligned with international reporting standards may be required to share seller/worker earnings data with HMRC annually. This doesn't change the underlying tax treatment, but it does mean assuming your fee income is visible to HMRC is the safer starting position, regardless of whether you're above or below the trading allowance.
Bottom line
Track fees separately from reimbursements, add up gross fees across the tax year, and register for Self Assessment only once that fee total exceeds £1,000 — the same trading allowance logic that applies to any other small side income.
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Frequently asked questions
Is the fee I'm paid for a mystery shopping assignment taxable?
Yes — the fee element (as opposed to reimbursement of a purchase you had to make) is trading income. If your total gross fee income from mystery shopping across a tax year is £1,000 or less, the trading allowance generally means it's tax-free and doesn't need reporting.
What about the cost of the meal or product I had to buy and then keep?
If you're reimbursed for a purchase you're required to make as part of the assignment and you get to keep the item (a meal, a haircut, a product), the reimbursement itself is not additional taxable income — it's simply covering a cost — but the item you keep may have a monetary value factored into how mystery shopping companies structure payments, so check the specific scheme's terms.
Do I need to register as self-employed for occasional mystery shopping?
Only once your gross fee income exceeds £1,000 in a tax year. Below that, most casual mystery shoppers doing a handful of assignments a year have nothing to register or report.
Can I claim mileage to assignments as an expense?
Yes, once registered for Self Assessment because income exceeds £1,000, mileage to genuine mystery shopping assignments is an allowable business expense, claimed at the standard 45p/25p rates or via actual vehicle costs, alongside the trading allowance or actual-expenses choice for the fee income itself.
Do mystery shopping companies report my earnings to HMRC?
Under the UK's rules requiring digital platforms to report seller/worker income to HMRC, some platform-based mystery shopping and gig-style schemes may report earnings data to HMRC annually, similar to other online marketplace and gig-economy reporting — treat all fee income as visible to HMRC regardless.
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