Everything from a single card to a 150-card lot — what USPS actually measures, where the toploader method stops working, and how to buy the right postage without guessing. Pokémon, Magic, Yu-Gi-Oh, sports: the method is the same.
Not card count. Three things, and every shipping decision below follows from them:
Thickness is the one that bites. Fifty cards in a single stack is nowhere near 1/4 inch. Fifty cards spread across three pockets lies flat and passes. Same cards, same weight, completely different outcome — which is why "how many cards fit" is the wrong question and "how is the thickness distributed" is the right one.
Exact counts per postage tier are in our cards-per-envelope chart.
Mostly no — and that is worth saying plainly, because it is the first thing people ask. Magic, Pokémon and modern sports cards are all 2.5" × 3.5", so every weight, thickness and postage number on this page applies to all of them identically. Yu-Gi-Oh cards are slightly smaller at 59 × 86 mm and behave the same, just a touch lighter each.
Four things do differ, and none of them are really about the game:
So if you are new to selling and you are shipping Pokémon, Magic, Yu-Gi-Oh or sports singles, this is the guide. The method is the same for all of them. Sort by weight and thickness, not by game.
For small orders this is still the right method and we use it ourselves. Stack the cards, slide the whole stack into a single penny sleeve, work that into a toploader, close the toploader with masking or painter's tape, drop it in a plain white envelope, and stamp it to weight.
Here is the part nobody writes down: you have to pry the toploader open to get six cards in. A standard toploader is built to take one card in a sleeve. A six-card stack in one sleeve is several times that thickness, so getting it seated means working the mouth open — most people use scissors or something similar to spread it — and toploaders crack doing this. Not often enough to stop you. Often enough that you should expect to lose some.
That is the honest ceiling of this method. It is cheap, it is available at every card shop, and it works fine up to about six cards if you do not mind the occasional split toploader.
It runs out for two different reasons, and it is worth being clear about which is which — because one is a hard wall and the other is a risk you have been carrying the whole time without being told.
The hard wall is physical. Six, maybe seven cards is all that fits in a penny sleeve and a toploader. Past that they simply do not go in. There is no technique for it. That number moves a little with sleeve thickness and card stock, but not much, and no amount of prying changes it.
The part nobody tells you: a loaded toploader in a plain white envelope is technically non-machinable already. A toploader is rigid, and letter automation wants a piece that bends. It goes through anyway, most of the time — that is tolerance, not compliance. You are not breaking the rules so much as quietly relying on USPS not to enforce them on a piece that small.
Which is why two toploaders is where it usually catches up with you. Two can get flagged as non-machinable — not always, but far more readily than one, and especially when they are loose enough to shift around inside the envelope. A piece that rattles and flexes unevenly is exactly what automation kicks out. So the second toploader does not just add thickness; it spends the tolerance the first one was living on.
So the honest picture at seven cards is not "you need a bubble mailer." It is that you have run out of room and run out of margin on a method that was never really machinable. The usual advice is to jump to a parcel and eat the postage. That jump is what costs sellers money — because the order itself has not changed. Only the packaging needs to.
The problem at this size is not weight — 50 raw cards is comfortably inside 3.5 oz. It is the 1/4 inch thickness limit, and the fix is to stop stacking.
The DIY version is the tape-and-cardboard sandwich: sleeve the cards, lay them between cardboard, tape the sandwich, tape it inside the envelope, hope the result stays flat and flexible. It works. It also costs a few minutes per order, puts tape near your cards, and goes rigid enough to trigger the surcharge if you build it badly.
The purpose-built version is an envelope with the pockets already in it. Cards slide into three built-in pockets that hold them flat and separated, the thickness stays distributed across the piece, and nothing sticky comes near a card. Load, peel, seal.
There is a difference here worth being precise about. The toploader method works on tolerance — it is a rigid piece that automation lets through most of the time. A distributed stack in a flexible envelope is a different thing: it bends, so it is machinable by design rather than by luck. That is the actual upgrade at this size. Not more capacity. Less dependence on being overlooked.
This is the envelope we make, so treat that paragraph accordingly — but the underlying principle holds whichever way you build it: distribute the stack, keep it flexible, or you will exceed 1/4 inch and stop being a letter.
Above roughly 50 raw cards you are past the letter limit and have a genuine decision to make. A 150-card lot can go as three letters or as one parcel, and the answer is closer than you might expect.
| 150 cards | Postage | Materials | Total | Tracking |
|---|---|---|---|---|
| Three First-Class letters | 3 × $1.69 = $5.07 | 3 × $0.35 = $1.05 | $6.12 | No |
| One Ground Advantage parcel | $6–8, by zone and size | ~$0.50 | $6.50–8.50 | Yes |
Commercial label pricing through eBay, Pirate Ship or PayPal. At the Post Office counter, Ground Advantage starts higher — USPS lists it from $7.90 — which widens the gap further.
Splitting still wins, but notice how much thinner the margin gets at this size. On a typical order — twenty cards, say — a letter costs about $1.46 against $6.50–8.50 for a parcel, and you are saving six to eight dollars every time. That is the whole economic case for letter-rate shipping, and it is not close.
At 150 cards you are buying three letters, so the saving drops to somewhere between forty cents and a couple of dollars, and you are putting three separate pieces in the mail instead of one. The parcel also comes with tracking, which the letters do not.
The way to think about it is per hundred orders, not per order. Ship a hundred small lots by letter and you save six to eight hundred dollars. Some small number of those go missing and you replace them. Unless your loss rate is far worse than most sellers see, the arithmetic is not close — which is why letter rate is the default in this guide rather than the exception.
The same logic holds at 150 cards, just at a smaller per-order margin. A dollar or two an order does not sound like much until you notice it is a dollar or two on every order, forever, against a loss you pay for occasionally. Ship two hundred lots that way and the saving is real money; the handful that go missing cost you the contents, not the order value — and on a bulk lot, the contents are commons.
That is the trade, stated plainly: you keep the postage difference on every order and you eat the occasional replacement. For anyone moving bulk lots, playsets and mid-value singles, that arithmetic has favoured letters for as long as parcel rates have been climbing, and it favours them more each time they climb again.
It only inverts when the contents get genuinely valuable — a lot where losing one of three pieces means replacing cards you cannot easily replace, or refunding an amount that dwarfs a year of postage savings. You know your own inventory. The question is not whether letters are cheaper. It is whether this particular lot is one you would shrug at losing.
Letter postage steps by ounce. Weigh the finished piece — guessing is how mail comes back.
| Weight | Postage | Roughly |
|---|---|---|
| 1 oz | $0.82 | ~10 raw cards |
| 2 oz | $1.11 | ~26 raw cards |
| 3 oz | $1.40 | ~41 raw cards |
| 3.5 oz (letter max) | $1.69 | ~50 raw cards |
USPS First-Class letter rates effective July 12, 2026. Penny-sleeved cards run roughly 25% fewer per tier.
Three ways to pay it, in rough order of how most sellers do it:
Do not skip the scale. Every problem in this section traces back to someone estimating the weight. A letter that arrives short-paid gets returned or the recipient gets billed, and neither ends well.
Letter postage does not come with a tracking number. That is the trade you are making for a $0.82–$1.69 shipment instead of a $7+ one, and it is worth understanding rather than discovering.
What you do get: every letter is barcode-scanned through USPS automation. Those scans feed Informed Delivery, the free USPS service that shows recipients images of mail arriving that day. It is not tracking and you cannot use it as proof of delivery in a dispute — but it does mean a letter is not invisible.
When one does not arrive: letters are slow before they are lost. Give it a full week past the expected date before treating it as missing — First-Class letters routinely take 3–5 business days and stragglers turn up at day 8 or 9. After that, USPS accepts a Missing Mail search request, though for a letter it rarely produces the piece.
The practical answer is to price the risk in. A small share of letters go missing. If your average order is a few dollars of cards, replacing the occasional one costs far less than paying tracked rates on every order.
The patent-pending trading card shipping envelope this guide is built around: 3-pocket strip, no tape, no toploaders, under 1/4" loaded.
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