How to Price Your Products When Tax Takes a Share: A Guide for UK Online Sellers

Most online sellers price by instinct. You look at what similar items are selling for, you decide what feels right, and you list it. If it sells, great. If the money coming in feels roughly acceptable, you carry on.

The problem with pricing by feel is that it ignores the one cost that is invisible until January: tax. By the time your Self Assessment return is due and your actual tax bill becomes clear, you've already sold hundreds of items at prices that looked profitable but weren't, at least not after HMRC took its share.

This post walks through exactly how tax should factor into your pricing decisions, with a calculator that tells you the minimum listing price you need to hit your target profit after platform fees and tax.

The Three Costs Most Sellers Ignore When Pricing

Platform fees are the obvious one. Most sellers know eBay takes roughly 12.8%, that Etsy has transaction and processing fees, and they adjust for that. What they don't adjust for, or don't adjust for correctly, are the other two.

The cost of stock. Not just what you paid for it, but what you need to recover before you're in profit at all. If you bought something for £12 and listed it for £18, you haven't made £6. You've made £6 minus fees minus the portion of your running costs attributable to that item. Start with the cost of acquisition before you think about margin.

Tax on the profit. Once you're trading and above the £1,000 trading allowance threshold, the profit you make from each sale contributes to your overall trading profit, which is taxed at your marginal rate. For a basic rate taxpayer that's 20% income tax plus 6% Class 4 National Insurance, a combined rate of 26% on trading profits. For a higher rate taxpayer the income tax element rises to 40%, making the combined rate 42%.

That is not a small number. A £10 profit on a sale, after fees and stock cost, becomes £7.40 in your pocket at the basic rate. Pricing without accounting for that is pricing with an invisible hole in your margins.

How Tax Changes the Minimum Viable Price

The maths behind tax-aware pricing is not complicated but it is different from what most people assume. Tax is not just deducted from your final number. It compounds through the calculation because fees reduce your gross income and tax is applied to what remains after costs.

Here is a worked example before the calculator. You bought a coat for £15. You're selling on eBay at 12.8% Final Value Fee. You're a basic rate taxpayer. You want to take home £10 clear after everything.

Without tax in the calculation, you might price at: £15 cost plus £10 target plus a rough allowance for fees, getting to something like £28 or £29. That feels about right.

With tax in the calculation the number is different. To net £10 after a 26% combined tax and NI rate and 12.8% eBay fees on a £15 item, you need to list at approximately £30.60. At that price, the fee is £3.92, leaving £26.68. After the £15 cost, your trading profit is £11.68. Tax and NI at 26% is £3.04, leaving you with £8.64. Still short of £10, which shows how easily the gap compounds if you stop the calculation one step too early.

Small differences per item compound across hundreds of sales. Use the calculator below to find the right number for your specific situation.

A Second Worked Example on Vinted

The same item priced on Vinted tells a different story, because Vinted charges sellers no fees at all. The buyer pays a separate protection fee on top of your listing price, so the full £30.60 you'd need on eBay isn't necessary here.

To net the same £10 after a 26% combined tax rate on a £15 item with zero platform fees, the required listing price is approximately £28.51. The trading profit is £13.51 (listing price minus cost), tax and NI at 26% is £3.51, leaving £10.00 net.

That's a £2.09 lower listing price than the eBay equivalent for the same net profit. For sellers who source the same stock and list across multiple platforms, this difference explains why identical items often need different prices depending on where they're listed, and why a single flat margin rule across platforms tends to under-price Vinted listings or over-price eBay ones.

What the Calculator Is Actually Telling You

A few things worth understanding about how the numbers work.

The tax rate used in the calculation includes Class 4 National Insurance as well as income tax, because both are charged on your trading profit. At the basic rate that means 26p in every pound of trading profit goes to HMRC, not 20p. At the higher rate it's 42p. If you've been mentally applying a 20% tax haircut to your profits, you've been underestimating the impact.

The calculation assumes you're trading above the £1,000 trading allowance threshold. If you're genuinely below £1,000 of gross income for the year, the tax element disappears and your minimum listing price drops accordingly. Select the zero tax option in the calculator if that applies to you.

The numbers are per-item approximations based on marginal rates. Your exact tax position depends on your total income across the year, whether you have a day job, any student loan repayments and other factors. For the precise figure, the UK Online Seller Tax Template calculates your complete position based on all your income and expenses throughout the year. The calculator here tells you whether your pricing strategy is broadly on track

How Tax-Aware Pricing Affects Your Payment on Account

There is a second-order effect worth knowing about, particularly if you are in your second year of Self Assessment. Pricing decisions made this tax year don't just determine this year's tax bill. They determine the size of your payment on account due the following January and July, because that payment is calculated as 50% of the previous year's tax liability, due in advance against the current year.

If you have been under-pricing and your actual profit comes in lower than expected, your payment on account for the following year is based on an artificially low base, which feels manageable until your profit genuinely grows and the gap between what you have paid in advance and what you actually owe widens. Pricing correctly from the start avoids this compounding effect and keeps your payment on account roughly in line with your actual trading activity. Our guide to saving the right amount for your tax bill covers how payment on account interacts with your monthly set-aside figure.

Pricing Strategy for Different Types of Sellers

If you are under the £1,000 trading allowance threshold: Tax doesn't affect your pricing yet. Your focus is on covering the cost of stock and platform fees and achieving a margin that makes the activity worthwhile. Once you approach £1,000 of gross income, revisit your prices with the calculator above.

If you are claiming the trading allowance: Your first £1,000 of gross income is deducted before tax applies. The effective tax rate on income above £1,000 is your marginal rate. For items sold when your income is below £1,000, price without the tax element. For items sold later in the year when you are above the threshold, use the calculator.

If you are claiming actual expenses: You have more deductions working in your favour than the calculator accounts for. Packaging, mileage and any other legitimate costs all reduce your taxable profit on top of platform fees. The calculator only factors in platform fees, so the price it gives you is a safe minimum. Once your full expenses are included, your actual tax bill will likely be a little lower than the calculator suggests, giving you slightly more room than the number shown. Our post on when not to claim the trading allowance covers how to choose the right approach for your numbers.

Which Categories Get Hit Hardest

Not every category absorbs the tax-and-fee combination the same way. Low-cost, high-fee items suffer the most because the fixed-fee components of platform charges, where they exist, eat up a larger proportion of a smaller sale price. A £6 item on Etsy, where a 20p listing fee and a 20p payment processing fee both apply regardless of sale value, loses a much bigger percentage of its value to fixed costs than a £60 item does.

High-margin categories like vintage or designer items tend to absorb tax and fees more comfortably because the absolute profit per item is larger even after the same percentage deductions. If your category mix leans toward low-value, high-volume items, it is worth running several of your typical price points through the calculator to check whether the volume is genuinely compensating for the thinner per-item margin, or whether you are working harder for less than it appears.

What to Do If Your Current Prices Don't Stack Up

If the calculator shows your current listing prices are generating less net profit than you thought, you have three options.

Raise your prices. The obvious answer and often the right one. Buyers on Vinted, eBay and Etsy are price-sensitive but not infinitely so. A £2 price increase on an item that was underpriced is usually absorbed without affecting sell-through rate.

Source more cheaply. If raising prices is not realistic for your category, the alternative is reducing the cost of stock. The maths works just as well from the other direction.

Adjust your category mix. Some categories carry higher fees, lower margins or slower sell-through rates than others. If you are selling items that consistently require heavy discounting to shift, the per-item economics may never work. Understanding the after-tax margin by category tells you where to focus sourcing effort.

Our multi-platform tax guide covers the combined income picture if you are selling across several platforms and need to understand your overall tax position alongside your per-item pricing.

Get the UK Online Seller Tax Template, £14.99 →