Priority Mail Cubic is a secret service you won't find at the Post Office, but it's the best way to ship small, heavier packages
Priority Mail Cubic is the cheapest, fastest way to ship small packages that weigh between 1 and 20 pounds.
USPS® will deliver Priority Mail Cubic packages to anywhere in the USA (and territories) within 1 to 3 days.
All Priority Mail Cubic packages included full door-to-door tracking, so you can keep an eye on your shipments.
Priority Mail Cubic postage purchased from Pirate Ship includes $100 of USPS® insurance for free.
Priority Mail Cubic pricing isn't available at the Post Office and it'll save you up to 89% off retail prices.
Businesses that optimize their packaging for USPS Cubic pricing unlock huge savings and efficiencies.
Pirate Ship offers Priority Mail Cubic rates BELOW Commercial Pricing® (the deepest discounts publicly available from USPS) with no markup, per-label costs, or monthly fees.
Priority Mail Cubic (or "Cubic" as it's commonly called) is a secret sub-service of Priority Mail® that’s usually only offered to businesses who ship at least 50,000 packages per year. But with Pirate Ship you can access even deeper discounts (below Commercial Pricing) with no minimum volume requirements.
The pricing for Priority Mail Cubic is based on the outer dimensions of your package, rather than the weight. There are 5 different tiers of pricing that your package could be in depending upon its size, and any box that's under half of a cubic foot in volume can qualify, as long as none of the dimensions go over the 18" maximum. You can ship up to 20 pounds for no extra cost, making it one of the cheapest shipping services available for small boxes.
To calculate which Cubic pricing tier your package is in:
Note that Priority Mail Cubic packages cannot be larger than 0.5, half of a cubic foot, but larger packages can be sent with weight-based Priority Mail.
You can also ship soft pack poly or padded envelopes with Priority Mail Cubic Softpack. Cubic Softpack pricing is the same as if you were shipping a box, but the formula for calculating the pricing tier is different.
To calculate which pricing tier a softpack envelope is in:
Note that neither dimension can be over 18", and the total size for Priority Mail Cubic Softpack cannot exceed 36". Larger envelopes can be sent via weight-based Priority Mail.
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