USPS

USPS Cubic Pricing

What is Cubic Pricing?

USPS Cubic Pricing is a way for customers to get lower shipping rates on small but heavy packages. To qualify for this affordable shipping option, packages must weigh 20 pounds or less and the longest dimension may not exceed 18 inches. Rolls and tubes do not qualify for mailpiece cubic prices.

With Cubic Pricing, customers get a rate based on the dimensions and shipping distance (zone) of a shipment. Since weight isn't a part of the shipping rates calculation for USPS Cubic Pricing, it's a great way for businesses to lower their shipping costs on small dense packages. Since all major carriers — including USPS, FedEx, UPS, and DHL — base their shipping rates on weight, Cubic Pricing provides savvy businesses opportunities to reduce their shipping rates on their small dense packages.

How Cubic Pricing Works

Cubic rate charts are broken down by zone and cubic tier, which is determined based on the volume of the item, not the weight. Priority Mail includes five tiers from 0.1 to 0.5. USPS Ground Advantage includes ten tiers from 0.1 to 1.0. The cubic tier is calculated in two ways depending on the type of packaging:

  • Rectangular and Nonrectangular
  • Soft Pack (poly, plastic, cloth, or similar soft packaging) and Padded Envelopes. Mailpieces that are pleated (e.g., expandable) must follow the measurement guidelines for Rectangular and Nonrectangular.

Regardless of the packaging type, the cubic tier calculated will determine your price based on cubic rate tables for each mail class.

Determining Cubic Tier Measurements for Rectangular and Nonrectangular Parcels

Measure in inches the length, width, and height at each dimension's maximum point. Round down each measurement to the nearest 1/4 inch. For example, 6-1/8" x 5-7/8" x 6-3/8" is rounded down to 6" x 5-3/4" x 6-1/4".

Multiply the length by the width by the height and divide by 1,728. For example: 6" x 5-3/4" x 6-1/4" = 215.6 divided by 1,728 = 0.125. (This piece exceeds 0.10 - Tier 1 threshold.) It is calculated at Tier 2: >0.10 up to 0.20.

TIER
MAILPIECES ...
CUBIC FOOT
0.10
measuring up to ...
0.10
0.20
measuring more than
0.10 up to 0.20
0.30
measuring more than
0.20 up to 0.30
0.40
measuring more than
0.30 up to 0.40
0.50
measuring more than
0.40 up to 0.50
0.60 *
measuring more than
0.50 up to 0.60
0.70 *
measuring more than
0.60 up to 0.70
0.80 *
measuring more than
0.70 up to 0.80
0.90 *
measuring more than
0.80 up to 0.90
1.00 *
measuring more than
0.90 up to 1.00

* USPS Ground Advantage only.

Determining Cubic Tier Measurement for Soft Pack and Padded Envelopes

Cubic tier measurements for soft pack and padded envelopes are based on the outside dimensions of length plus width, in inches, of the flat original packaging material before it is loaded with items.

Measure the length and width separately in inches.

Round down each measurement to the nearest 1/4 inch. For example, 10-1/8 inches is rounded down to 10 inches.

Add the two measurements and use the tables below, depending on mail class, to determine which cubic tier applies.

Note: There are different dimension values for each Soft Pack and Padded Envelope tier between Priority Mail and USPS Ground Advantage.

Priority Mail Cubic-Pricing Tiers for Soft Pack and Padded Envelopes

CUBIC-PRICE TIER
MAILPIECES MEASURING...
CUBIC FOOT
0.10
from ...
0" up to 21"
0.20
more than ...
21" up to 27"
0.30
more than ...
27" up to 31"
0.40
more than ...
31" up to 34"
0.50
more than ...
34" up to 36"

USPS Ground Advantage Cubic-Pricing Tiers for Soft Pack and Padded Envelopes

CUBIC-PRICE TIER
MAILPIECES MEASURING...
CUBIC FOOT
0.10
from ...
0" up to 16"
0.20
more than ...
16" up to 21"
0.30
more than ...
21" up to 24"
0.40
more than ...
24" up to 26"
0.50
more than ...
26" up to 28"
0.60
more than ...
28" up to 30"
0.70
more than ...
30" up to 32"
0.80
more than ...
32" up to 34"
0.90
more than ...
34" up to 35"
1.00
more than ...
35" up to 36"

Regardless of the packaging type, the cubic tier calculated will determine your price based on cubic rate tables for each mail class.

See Cubic Pricing on the USPS Rates Page

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