66 lb is a real wall for some groups
Group 1's column in the price file goes blank past 66 lb. A 68 lb parcel to Canada under weight-based Priority Mail International has no listed price at all, regardless of what the general 70 lb figure implies.
USPS, weight-based side
Priority Mail International's weight-based price ladder, in full
Every USPS page that quotes an international starting price is quoting the lightest package to the cheapest group. The actual ladder climbs on two axes at once — weight and destination group — and USPS's own June 2026 retail price file breaks that second axis into twenty groups, not the eight most people have seen on a flat rate chart. What follows is that file, read directly, at six weight breakpoints across three of the twenty groups.
Read from usps.com2026-09-0120 destination groups, not 8
Two axes, not one
Weight sets the row. Destination group sets the column. A single starting price only ever shows one cell.
Six weights, three of the twenty groups
USPS's price file runs one row per pound from 1 lb up to 70 lb, times twenty columns. Printing all of it would be unreadable, so the table below samples six weights against Group 1 (labeled Canada in the file itself), Group 7, and Group 12 — the group that runs most expensive at the higher weights sampled here.
| Weight | Group 1 (Canada) | Group 7 | Group 12 |
|---|---|---|---|
| 1 lb | 43.55 USD | 67.05 USD | 70.65 USD |
| 5 lb | 59.05 USD | 94.15 USD | 106.65 USD |
| 10 lb | 86.25 USD | 133.70 USD | 166.15 USD |
| 20 lb | 140.65 USD | 212.70 USD | 258.80 USD |
| 40 lb | 198.95 USD | 327.25 USD | 435.20 USD |
| 66 lb | 305.95 USD | 472.45 USD | 686.50 USD |
Group 1 barely more than triples in price for a jump from 1 lb to 66 lb — sixty-six times the weight. Group 12 rises nearly tenfold over the same span, and by 66 lb it has pulled well ahead of Group 7 even though the two started less than four dollars apart at 1 lb. Weight and destination group interact; neither one predicts the total on its own.
Two group systems in the same file, not one
USPS's flat rate envelope and boxes price across 8 destination groups, covered on our companion page on flat rate shipping by country group. The weight-based Priority Mail International table sitting in the same price file runs 20 separate groups instead, with no published key linking a country's flat rate group number to its weight-based group number. A country in flat rate Group 3 is not necessarily in weight-based Group 3 — they are two different classification schemes that happen to share small integers.
The file names exactly one group directly: Group 1 is labeled Canada, both in the flat rate table and here. Every other group in the weight-based table is a bare number with no country attached in the file itself, which is why the table above is described by group number only rather than by naming a country to Group 7 or Group 12.
The published ceiling is not what the price file actually allows
USPS's Priority Mail International product page states a 70 lb general maximum. The price file tells a more specific story: several groups, Group 1 and Group 12 among them, stop printing a price at 66 lb, four rows short of that stated ceiling, while other groups continue pricing all the way to 70 lb.
Other groups run the full 70 lb
Groups 2, 3, 6, 7, 8, 9, 10 and 16 all carry a price through 70 lb in the same file. The ceiling genuinely differs by destination group, not just by a footnote on the general page.
The general product page will not tell you which is which
Nothing on USPS's main Priority Mail International page distinguishes the groups that stop at 66 lb from the ones that run to 70. The price file itself is the only place that distinction actually shows up.
The 4 lb alternative underneath all of this
Weight-based Priority Mail International is not the cheapest way to send something small overseas. First-Class Package International Service caps out at 4 lb and starts well below the weight-based floor shown above, trading away the higher weight ceiling and the merchandise coverage that comes with Priority Mail International in exchange for a lower price on light parcels. The full service, its coverage terms and its published starting figure are covered on USPS international shipping, priced and explained rather than repeated here.
None of the USPS products on this page are sold through SMKlog's checkout. What checkout does sell is courier labels to four countries — Canada, the United Kingdom, Germany and Australia — on FedEx, UPS and DHL Express, each with the customs declaration completed before payment. Anyone comparing a postal quote against a courier one should price the actual box on both sides rather than assume either is cheaper by default.
Where these figures come from
- USPS, Priority Mail International, Retail price file — weight-based prices by pound across all 20 destination groups, effective 6/15/2026. Read 2026-09-01.
- USPS, Priority Mail International — the general 70 lb weight ceiling and the weight-and-destination pricing statement. Read 2026-09-01.
USPS revises its price files each time prices change, without individual notice on this page. Treat the figures above as what the June 2026 file stated, and check the current file before budgeting a shipment.
Weight-based Priority Mail International, unpacked
How much does weight-based Priority Mail International cost per pound?
It does not move in a straight line per pound, and it depends on the destination group. To the cheapest group (Canada), USPS's own June 2026 retail price file prices 1 lb at 43.55 USD and 20 lb at 140.65 USD — roughly 3.2 times the price for 20 times the weight. To a costlier group, the same jump runs from about 67 USD to 213 USD.
Is the weight-based price the same country grouping as the flat rate boxes?
No, and this trips people up. The flat rate envelope and boxes are priced across 8 destination groups. The weight-based Priority Mail International table in the same price file runs 20 separate destination groups instead, and USPS does not publish a shared key mapping one set of group numbers to the other.
What is the maximum weight for Priority Mail International?
USPS's general product page states 70 lb, but the price file itself does not honor that ceiling evenly. Group 1 (Canada) and several other groups stop printing a price at 66 lb, several rows before the stated 70 lb maximum, while other groups price all the way to 70.
Does a lighter, cheaper USPS service exist for international packages?
Yes. First-Class Package International Service is capped at 4 lb and starts well under Priority Mail International's weight-based floor, trading the 70 lb ceiling and the merchandise coverage for a much lower price on small, light parcels.
Can I buy a weight-based USPS international label through SMKlog?
No. SMKlog's checkout sells courier labels to four countries — Canada, the UK, Germany and Australia — on FedEx, UPS and DHL Express, not USPS postal products. The figures on this page are USPS's own published prices, shown for comparison, not something bought here.