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Weight-based Priority Mail® is the cheapest way to ship large packages

Weight-based Priority Mail® is the cheapest way to ship, unless your package qualifies for Priority Mail Cubic® or is large but light

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  • 📦

    Cheapest for large packages

    Weight-based Priority Mail® is the cheapest, fastest way to ship packages that are over half a cubic foot in volume.

  • Delivery in 1 to 3 business days

    USPS® delivers Priority Mail® packages to anywhere in the USA and its territories within 1 to 3 days.

  • 📡

    Free package tracking included

    Priority Mail® shipments include full tracking from door-to-door, so you'll always know where your shipments are.

  • 💥

    $100 insurance included for free

    All Priority Mail® postage bought with Pirate Ship includes $100 of insurance from USPS® for free.

  • 💵

    Save up to 41% by using Pirate Ship

    Commercial Plus Pricing® for Priority Mail® will save you up to 41% compared to paying retail prices.

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Get the cheapest Priority Mail® rates

Unlike other places to buy USPS® postage online, Pirate Ship passes through Commercial Plus Pricing® for Priority Mail® with absolutely no markup, fees, or monthly costs. So you get the deepest discounts available for free, with no risks or commitments. 

Weight
Up to, not over
0-150 miles
L, 1 & 2
150-300 miles
Zone 3
300-600 miles
Zone 4
600-1000 miles
Zone 5
1000-1400 miles
Zone 6
1400-1800 miles
Zone 7
1800+ miles
Zone 8
Territories
Zone 9
1 lb
$6.35
$6.79
$6.89
$6.98
$7.13
$7.28
$7.53
$9.72
2 lb
$6.89
$7.03
$7.18
$7.91
$9.19
$9.98
$10.48
$14.87
3 lb
$6.98
$7.45
$8.22
$8.98
$11.80
$12.76
$14.88
$20.18
4 lb
$7.09
$7.81
$8.43
$10.03
$13.75
$15.59
$17.61
$24.30
5 lb
$7.19
$8.17
$9.09
$10.33
$15.67
$17.92
$20.40
$28.28
6 lb
$7.29
$7.29
$9.42
$13.77
$17.58
$20.42
$23.35
$32.40
7 lb
$7.80
$9.35
$9.74
$15.13
$19.47
$23.03
$26.23
$36.38
8 lb
$8.24
$9.63
$10.99
$16.84
$21.39
$25.35
$29.45
$40.85
9 lb
$8.46
$9.90
$11.07
$18.06
$23.27
$27.45
$32.74
$45.42
10 lb
$8.95
$10.18
$11.12
$19.51
$25.13
$30.19
$35.61
$49.39
11 lb
$10.46
$12.52
$13.42
$20.89
$26.98
$32.85
$38.57
$53.96
12 lb
$11.10
$13.32
$15.62
$22.37
$29.42
$35.52
$41.37
$57.86
13 lb
$11.68
$14.07
$16.35
$23.55
$31.58
$36.96
$42.84
$59.92
14 lb
$12.28
$14.85
$17.22
$24.94
$33.35
$39.01
$44.96
$62.89
15 lb
$12.76
$15.63
$18.06
$26.22
$34.64
$39.76
$46.14
$64.55
16 lb
$13.19
$16.46
$19.04
$27.52
$36.61
$42.00
$48.68
$68.10
17 lb
$13.61
$17.22
$19.95
$28.86
$38.46
$44.18
$51.26
$71.68
18 lb
$13.87
$17.75
$20.85
$30.16
$40.50
$46.36
$53.84
$75.31
19 lb
$14.20
$18.17
$21.32
$30.95
$42.31
$48.52
$56.39
$78.87
20 lb
$14.76
$18.45
$21.76
$31.52
$43.41
$50.33
$59.00
$82.51
21-70 lbs
To see all USPS® Priority Mail® weight-based rates, view or download the rate sheets below
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For large but light packages, watch out for Priority Mail® dimensional weight pricing

Dimensional weight is common for every carrier, basically because they don't want to fill up their trucks and planes with packages that are large but mostly empty & light.

If your package is larger than 1 cubic foot (for example, if the dimensions are 13" x 13" x 13") then USPS® uses a formula to calculate the minimum rate they will charge. It's based off the dimensions, which is why this is known as the "dimensional weight" or "DIM weight". If your package's dimensional weight is "heavier" than the actual weight, you will be charged as if your package were that heavier weight.

Dimensional weight is calculated by multiplying a package's length, width, and height and then dividing by the volumetric divisor. USPS® uses 194 for their divisor, which is much more competitive than the other carriers. Even more competitively, USPS® only applies dimensional weight pricing to packages in zones 5-9.

So for an example of a package that measures 13" x 13" x 13", you would multiply the three dimensions to get 2197, and then divide that by 194 to get 11.32, which is the dimensional weight. So if your package's actual weight was less than 11.32 pounds, you would get charged the 12 pound Priority Mail® rate for zones 5-9. If your package was more than 11.32 pounds, the dimensional weight would be disregarded and you would just be charged the actual weight.

Dimensional Weight can make it more expensive to use Priority Mail® for a large box than it would be if you used Parcel Select Ground®, but Priority Mail® is a much faster service and includes $100 of insurance.

Tropical leaf and coaster

For very big packages, watch out for Priority Mail® Balloon Rate

If your packages are very large, be aware of USPS® balloon rate pricing. If your package's Length (longest side) + Girth (Width * 2 + Height * 2) is between 84" and 108", for zones 1-4 you will pay postage at the 20-pound rate rather than the actual weight rate.

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