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 22 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. Starting July 12, 2026 it includes five tiers from 0.1 to 0.5.
The cubic tier calculated will determine your price based on cubic rate tables for each mail class.
Determining Cubic Tier Measurements for 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 |
Cubic-Pricing Tiers
| 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″ |
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
