What does the postage calculator work out?
It takes four steps from what you tell it: the weight of the parcel, whether that fits a Large Letter, which weight band it falls in, and what Royal Mail charges for each service in that format. It then names the cheapest service that tracks the parcel, if you want tracking, and covers the amount you want covered, if you give one.
What weights does it assume?
These are our own estimates for a typical card parcel, not Royal Mail figures. Weigh the finished parcel on kitchen scales: Royal Mail goes by the real weight and size.
| Item | Weight |
|---|---|
| A card in a penny sleeve | 2 g |
| A toploader | 9 g |
| Paper slip and tape over the toploader opening | 1 g |
| Board-backed envelope with two pieces of stiff card | 25 g |
| Padded bubble mailer with two pieces of stiff card | 40 g |
| Small box and filler, for a stack too thick for an envelope | 60 g |
| One graded slab | 60 g |
| Bubble wrap for one slab | 10 g |
| Padded mailer or small box around the slabs | 50 g |
A card in a toploader with its slip and tape comes to 12 g, so one card in a board-backed envelope is about 37 g. Thickness is assumed too: each toploader adds 0.4 cm, a board-backed envelope about 0.8 cm and a padded mailer about 1.6 cm. One wrapped slab in a padded mailer comes to about 2.3 cm.
Large Letter or Small Parcel?
Royal Mail’s Large Letter limit is 35.3 x 25 cm, 2.5 cm thick and 750 g. A Small Parcel is up to 45 x 35 x 16 cm and 2 kg. Four toploaders in a board-backed envelope come to about 2.4 cm, so they just fit as a Large Letter; five are about 2.8 cm and post as a Small Parcel, which costs more. Our postage guide covers the sizes and how to pack a card so it survives the post.
Which service should I choose?
Royal Mail’s compensation is what separates the services. 2nd Class pays up to £20 and has no tracking, Tracked 48 and Tracked 24 pay up to £75, and Special Delivery by 1pm pays up to £750, £1,000 or £2,500 depending on the cover you buy. Tell the calculator how much you want covered and it picks the cheapest service that reaches it.
Tracking is recommended for anything you would mind losing: it shows the parcel was delivered, and Royal Mail advises getting evidence of posting for items of value. For an untracked parcel, ask the Post Office for a certificate of posting and keep it as proof of postage. Compensation also depends on packing: an item that can bend must be in a strong container and marked DO NOT BEND above the address, or a claim can be refused. The postage guide has the rules.
How up to date are the prices?
Royal Mail changes its prices more than once a year, and the latest change took effect on 5 October 2026. These are the prices valid from that date, read on 17 October 2026. Royal Mail’s own tables are listed under Sources. The 2nd Class Large Letter prices above 100 g and the Small Parcel prices were confirmed from trade summaries of those tables, and any online price we could not confirm is marked. Check Royal Mail’s price finder before you buy postage.
Questions people ask
How much does it cost to post a Pokémon card in the UK?
For one card in a board-backed envelope, a 2nd Class Large Letter up to 100 g costs £1.55. It has no tracking and compensation up to £20. If you want tracking, Tracked 48 online costs £2.90 for a Large Letter. These are Royal Mail’s prices from 5 October 2026.
Is a card in a toploader a Large Letter or a parcel?
A toploader is thin enough for a Large Letter, which can be up to 2.5 cm thick. On our assumptions, up to four toploaded cards in a board-backed envelope fit that limit. Five or more make a stack too thick, and the parcel is a Small Parcel. Measure the finished parcel to be sure.
How much does a Pokémon card weigh in the post?
A card in a penny sleeve is about 2 g and a toploader about 9 g, so a toploaded card is roughly 12 g. The packaging weighs more than the cards: one card in a board-backed envelope comes to about 37 g. These are our estimates, so weigh your own parcel.
Do I need tracking to post a Pokémon card?
Royal Mail does not require it, but 2nd Class has no tracking and pays out at most £20. Tracking is worth having for anything you would mind losing, because it shows delivery. For an untracked parcel, get a certificate of posting from the Post Office and keep it as proof you sent it.
Can I post a graded slab as a Large Letter?
Sometimes. One slab wrapped in bubble wrap in a padded mailer comes to about 2.3 cm on our assumptions, just inside the 2.5 cm limit. Two slabs usually will not fit. Measure the wrapped slab before you buy postage, because a parcel over 2.5 cm thick is a Small Parcel and costs more.
Are these Royal Mail’s current prices?
They are the prices valid from 5 October 2026, read on 17 October 2026. Royal Mail changes its prices more than once a year, so check its price finder or published tables before you buy postage. The calculator shows when its figures were read every time you use it.
Sources
- Royal Mail: Online prices, valid from 5 October 2026 (published by Royal Mail; figures checked from extracts and trade summaries, not opened directly), read 17 October 2026
- Royal Mail: Our prices (Post Office), valid from 5 October 2026 (published by Royal Mail; figures checked from extracts and trade summaries, not opened directly), read 17 October 2026
- Royal Mail: Prices 2026, read 17 October 2026
- Franking Machine Supplies: Royal Mail postage rates, October 2026 update (summary of stamp prices), read 17 October 2026
- Angler Fulfilment: Royal Mail price increase, October 2026 (summary of small parcel prices), read 17 October 2026
Last updated 17 October 2026.