A boxed suitcase sits well inside the size ceiling USPS sets for the UK: 66 lb, 60 inches on the longest side, 108 inches of length plus girth combined. What trips people up on this lane is not the tape measure, it is the pocket knife left in a jacket zipped inside the case — the UK's own listing bars kitchen knives outright, wider than most countries this site has checked. Figures below are read from USPS's individual country listing for the United Kingdom on 2026-08-19.
Size clears with margin. The UK's knife rule is the one worth reading twice.
Read 2026-08-19 from USPS's Individual Country Listing for the United Kingdom at pe.usps.com/text/imm/tz_018.htm: Priority Mail International there tops out at 66 lb, a maximum single-side length of 60 inches, and a maximum combined length and girth of 108 inches. The listing treats England, Scotland, Wales, Northern Ireland and the Channel and Irish Sea islands as one entry.
| Measurement | This suitcase | UK's limit |
|---|---|---|
| Weight | 30 lb | 66 lb |
| Longest side | 30 in | 60 in |
| Length + girth | 96 in | 108 in |
Twelve inches of headroom on length plus girth, and half the length ceiling left unused. On this lane the size rule is rarely the reason a bag gets refused; the contents list is.
Most country listings this site has read restrict fixed-blade or automatic knives and leave ordinary cutlery alone. The United Kingdom's listing does not draw that line, per the reading on 2026-08-19.
A boxed set of steak knives packed alongside kitchen items for a move sits on the same footing as a fixed-blade hunting knife under this rule. Check every pocket and every zipped compartment of a suitcase before it ships, not just the obvious ones.
Per the listing read 2026-08-19, Priority Mail International to the UK needs a customs form, PS Form 2976-A inside the plastic PS Form 2976-E envelope, on every parcel regardless of what is inside. What a UK recipient actually owes at the door — the GBP 135 duty threshold, the GBP 39 gift exemption, and how VAT is calculated on the total package value — is worked through with its own sourcing on our shipping to the UK guide, so it is not repeated here.
Our checkout produces United States domestic parcel labels, not a UK-bound one. For scale, here is a domestic run toward an East Coast gateway city: a 22 × 14 × 9 in carry-on case, 18 lb, Newark, NJ 07102 to Miami, FL 33101, quoted live 2026-08-19.
| Carrier | Service | Price | Estimated transit |
|---|---|---|---|
| UPS | Ground Saver | $25.24 | about 5 business days |
| FedEx | SmartPost | $25.25 | 6-7 business days |
| UPS | Ground | $30.08 | 5-6 business days |
| USPS | Ground Advantage | $29.62 | 8-9 business days |
| FedEx | Ground | $40.43 | 5-6 business days |
UPS Ground Saver and FedEx SmartPost landed within a penny of each other, both well ahead of USPS Ground Advantage's own domestic rate on the same box. This is a domestic price only, a benchmark for what a boxed carry-on costs to move inside the country; the transatlantic mile is sold by USPS, UPS or FedEx directly.
USPS updates its country listings on its own schedule, and the knife rule in particular is worth a second look close to a shipment date. This page carries one dated snapshot, read 2026-08-19, not a live feed of the listing itself.
Size-wise, easily. USPS's individual country listing for the United Kingdom, read 2026-08-19, caps Priority Mail International at 66 lb, 60 inches on the longest side, and 108 inches of length plus girth combined. A 30 x 20 x 13 in boxed suitcase we measured comes to 96 inches of length plus girth, 12 inches under that line, and 30 inches under the length limit.
No. The UK's listing bars kitchen knives regardless of size or design, along with utility knives and box cutters, more broadly than most country listings this site has read. Pull any blade out of a packed suitcase before it ships there, ordinary cutlery included.
No. The calculator prices United States domestic parcels between two ZIP codes. A suitcase headed to the UK is bought through USPS, UPS or FedEx directly, or through freight review if the shipment needs a person to price it.
Full VAT and duty rules for the UK, sourced to gov.uk with the GBP 135 duty threshold and the GBP 39 gift exemption, are covered in depth on our shipping to the UK guide. This page covers the size and prohibited-items side of a mailed suitcase specifically.
$25.24 on UPS Ground Saver for our 22 x 14 x 9 in, 18 lb carry-on case, Newark, NJ to Miami, FL, quoted 2026-08-19, with FedEx SmartPost one cent behind at $25.25. That is the domestic leg only, useful as a benchmark; it is not a price for the transatlantic mile the parcel still has to cross.
Runs SMKlog and its live rate comparisons across USPS, UPS, and FedEx. The guides here are built from the same carrier data the calculator quotes from, with prices captured on the date shown on each page. Based in Berkeley Heights, New Jersey.