What is USPS Priority Mail Cubic Pricing?

USPS Priority Mail Cubic is a cost-effective shipping option for small, dense packages. This service allows you to ship packages up to half a cubic foot in volume (equivalent to 12x12x6 inches or other combinations with the same volume) and weighing up to 20 pounds. To qualify for Cubic rates, the maximum size for any dimension is 18 inches.

Priority Mail Cubic pricing is based on the package's outer dimensions rather than its weight, making it an excellent choice for businesses looking to optimize their shipping costs. By strategically planning your packaging to fit within the smallest pricing tier possible for your package's contents, you can significantly reduce shipping expenses.

How to Calculate Priority Mail Cubic Pricing Tiers

Priority Mail Cubic has five pricing tiers based on the package's cubic volume. To determine which tier your package falls into, follow these steps:

Measure your package's outer length, width, and height.
Round down any measurements that exceed the nearest quarter inch to the nearest quarter inch (e.g., 5.6 inches becomes 5.5 inches).
Multiply the package's length, width, and height, then divide the result by 1728 to calculate the cubic feet.

For example, to calculate the Cubic tier for a box measuring 12.3" x 9.5" x 3":

Round down the dimensions to 12.25" x 9.5" x 3".
Multiply 12.25" x 9.5" x 3" to get 349.125.
Divide 349.125 by 1728, resulting in approximately 0.202 cubic feet.
Since this package is just over 0.2 cubic feet, it would fall into the 0.3 cubic feet pricing tier.
If the box were slightly smaller (e.g., 12" x 9.5" x 3"), it would be in the 0.2 pricing tier and cost up to 25% less to ship.

Using Priority Mail Cubic with Envelopes and Poly Mailers

Priority Mail Cubic can be used with envelopes or poly mailers, but using padded envelopes or poly softpacks will impact the formula for determining your pricing tier. It's important to note that Cubic-priced mailpieces cannot be rolls or tubes.

Optimizing Your Packaging for Priority Mail Cubic

To make the most of Priority Mail Cubic pricing, carefully plan your packaging to fit within the smallest tier possible for your package's contents. This approach can lead to significant cost savings. Consider the following tips:

Choose packaging materials that minimize empty space and protect your products.
Experiment with different packaging configurations to find the most cost-effective solution.
Regularly review your packaging strategy to ensure you're consistently optimizing for the lowest pricing tier.

Priority Mail Cubic Rates and Pricing Tiers

Priority Mail Cubic rates vary based on the package's cubic volume and the shipping distance. The five pricing tiers are:

Cubic Tier 0.1: Up to 0.1 cubic feet
Cubic Tier 0.2: Over 0.1 to 0.2 cubic feet
Cubic Tier 0.3: Over 0.2 to 0.3 cubic feet
Cubic Tier 0.4: Over 0.3 to 0.4 cubic feet
Cubic Tier 0.5: Over 0.4 to 0.5 cubic feet

Rates for each tier are determined by the shipping distance, with prices increasing for longer distances. To find the most current rates for your specific shipping needs, consult the official USPS rate charts or use a reliable shipping software solution.

Calculating Your Package's Cubic Tier

For Boxes and Rigid Packages:

Measure the outer dimensions (length, width, height) in inches
Round each measurement down to the nearest quarter inch
Multiply length x width x height
Divide the result by 1728 (cubic inches in a cubic foot)
The result is your package's cubic feet measurement

Example: For a box measuring 12.3" x 9.5" x 3":

Round down to 12.25" x 9.5" x 3"
12.25 x 9.5 x 3 = 349.125
349.125 / 1728 = 0.202 cubic feet
This package falls into the 0.3 cubic feet pricing tier

Note: Maximum size for any single dimension is 18 inches

For Envelopes and Soft Packs:

Measure the length and width of the empty envelope
Round down to the nearest quarter inch
Add the length and width together
Use the total to determine the pricing tier:
- Tier 0.1: Up to 21"
- Tier 0.2: 21.01" to 27"
- Tier 0.3: 27.01" to 31"
- Tier 0.4: 31.01" to 34"
- Tier 0.5: 34.01" to 36"

Restrictions

Tubes and rolls are not eligible for Cubic pricing
Maximum combined length and girth is 84 inches

Benefits of Using Priority Mail Cubic

Cost savings: Cheaper than weight-based pricing for small, heavy items
Predictable pricing: Easy to calculate shipping costs based on box dimensions
Fast delivery: 1-3 business day delivery to any US address, including PO boxes
Free tracking: Monitor shipments at no extra cost
Included insurance: $100 of coverage with every shipment
No surcharges: Residential and fuel surcharges included in the price

Tips for Maximizing Savings

Optimize packaging: Use the smallest box possible that safely fits your items
Consider breaking up large orders: Sometimes shipping in multiple smaller boxes can be cheaper
Use cubic feet calculators: Online tools can help quickly determine your package's tier
Compare rates: Always compare Cubic rates with other shipping methods
Use Commercial Pricing: Accessing Commercial Pricing rates can lead to even more savings

2024 USPS Priority Mail Cubic Rates

Accessing Priority Mail Cubic Rates

Priority Mail Cubic isn't available at regular Post Office counters. However, many online shipping platforms and 3PL providers offer access to these rates. By partnering with a fulfillment provider, you can easily access these discounted rates and streamline your shipping process. For small-scale sellers not yet ready for a 3PL, Pirate Ship offers free access to USPS Priority Mail Cubic rates with no monthly fees or minimums.

Understanding USPS Priority Mail Cubic: Pricing, Tiers, and Optimization

Explore the benefits of USPS Priority Mail Cubic and learn how to calculate pricing tiers based on package dimensions. Discover tips for optimizing your packaging and access true Commercial Pricing through Simpl Fulfillment to maximize your shipping cost savings.