PayoutMath
Seller guide

Shipping supplies cost per order (UK)

Most UK sellers underestimate packaging cost by 30-50%. Here's how to actually price it in.

Last updated 10 May 2026

If you sell physical goods, your cost per order has at least three line items: the product itself, the postage label, and the supplies you wrap it in. Most UK sellers track Royal Mail or Evri postage carefully, watch the product cost, and quietly let the third line item wander.

This is a problem because supply cost compounds. A polythene mailing bag costs about 8p. A printed shipping label costs another sheet of paper at maybe 2p. Tape, 5p. Filler, 15p if you use anything. Add a thank-you card and you're at 30-50p per order before the postage even hits.

On a £20 t-shirt with 30% margins after platform fees, 50p is two and a half percentage points of profit. Multiply across 1,000 orders a year and supplies are £500 you didn't budget for.

What "supplies" actually includes

Worked example: a t-shirt order

Bella+Canvas 3001 unisex tee in a polythene mailer:

Total: 23p per t-shirt order.

That's the floor — assuming thermal labels (no ink cost) and you skipped the sticker. Most UK sellers using inkjet labels and bubble mailers are closer to 50p per order on supplies alone.

Worked example: a ceramic mug

Mugs are different — they need actual protection. A typical UK setup:

Total: 92p per mug order.

This is much bigger proportionally. A £14.95 mug with £4.99 shipping has gross revenue of £19.94. After Etsy UK fees that's around £17.50 take-home. With £6.95 base cost plus 92p supplies plus £4.50 first-item shipping, you're at £12.37 in costs — a £5.13 profit, or ~26% margin. Forget the supplies line and you'd think you were making £6.05.

Worked example: small jewellery

Jewellery often goes in smaller mailers with display cards:

Total: 47p per jewellery order.

The display card alone often justifies itself in perceived value — a £12 pair of earrings on a branded card photographs better and feels more giftable. The cost is real but it's customer-experience spend, not just packaging.

The biggest leaks (and how to plug them)

Leak #1: Inkjet labels

Inkjet ink is staggeringly expensive — somewhere between 8p and 25p per shipping label depending on cartridge yield. A thermal label printer pays for itself within 100-200 orders if you ship enough volume. After that, every label costs you about 2p in paper and zero in ink. Both Royal Mail Click & Drop and the major Evri integrations support thermal printers natively.

Leak #2: Wrong-sized boxes (and Royal Mail bands)

Royal Mail Tracked 24/48 has small/medium/large parcel size bands, and an oversized box can push you up a band even when the contents would fit a smaller one. The price difference between Small Parcel and Medium Parcel is usually £1-2 — multiplied by orders, this becomes real money fast.

The fix is keeping a range of box sizes on hand and matching the box to the product. A 10-box assortment costs maybe £15 and saves you from over-packing every order.

Leak #3: Not weighing before booking

Royal Mail and Evri both charge by weight band. A £15 postal scale pays for itself in the first month if you ship more than a few orders a week. The accidental overpay from picking the wrong weight band is the most common margin leak.

Leak #4: Buying retail at the post office

Post Office prices for boxes and supplies are 30-50% above what you can buy in bulk online. The exception is some Royal Mail packaging which is free or low-cost — but anything else, buy in bulk packs.

How to actually track this

Two approaches, both work:

Per-product: Calculate supply cost for each SKU once and bake it into your COGS. T-shirt = 23p. Mug = 92p. Necklace = 47p. Use those numbers in your Etsy UK fee calculator or Printful UK calculator as part of "cost of goods" rather than zeroing it out.

Per-month: Add up everything you bought from the supply category in a month, divide by orders shipped. Faster but less actionable — average across all products, not where the problem is.

HMRC tax note

Shipping supplies are an allowable business expense for self-employed sellers. They reduce your taxable profit on your Self-Assessment return. Track them — keep receipts, or use a receipt scanner to digitise as they come in. If you're under the £1,000 trading allowance you can ignore expenses entirely; above that, use either the trading allowance OR actual expenses but not both. See the trading allowance calculator for the choice.

VAT considerations

If you're VAT-registered, packaging supplies usually carry 20% VAT which you can reclaim. If you're not VAT-registered, the cost is just the cost — no reclaim. The VAT calculator covers the threshold maths.

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