Follow

USPS Priority Mail: Weight Rates vs Flat Rate Green (dimensional)

Created:   |   Updated:

Welcome to the USPS Priority Mail guide to domestic service and package rates series. Learn how to use this guide.

In this guide, we compare specific USPS Priority Mail services: weight-based rates and Flat Rate Green, ShippingEasy's exclusive dimensional rates. Learn more about USPS Priority Mail.

Overview of service comparison:

With either weight-based services and ShippingEasy's dimensional rates under Flat Rate Green, shippers use their own packaging. Both rates rely on zone based pricing, meaning that rates increase as the distance (zone) increases. Learn more about USPS zones.

Weight-based services offer the most flexibility. With minimal restrictions, package girth may not exceed 108" inches and the total weight must be less than 70 lbs. As the name indicates, weight is a factor in determining postage costs.

In the case of Flat Rate Green, specific package restrictions apply:

  • Weigh less than 20 lbs
  • Volume may not exceed 0.50 cu ft
  • No dimension longer than 18 inches

Flat Rate Green rates are based on package dimensions. By keeping packaging small, larger discounts are available. A tiered system is used to define package dimensions:

  • Tier 1: less than 0.10 cu ft
  • Tier 2: less than 0.20 cu ft
  • Tier 3: less than 0.30 cu ft
  • Tier 4: less than 0.40 cu ft
  • Tier 5: less than 0.50 cu ft

With Flat Rate Green, smaller packages ship for less than larger ones, when comparing similar destinations. Before comparing rates, it's best to determine if your packages qualify for Flat Rate green. Learn more about Flat Rate Green and dimensional pricing.

In general, you'll see the greatest advantage with weight-based rates for very-light, very-heavy, or very-large packages. In most other cases the dimensional rates with Flat Rate Green will be lower. If package dimensions are entered, ShippingEasy will always quote the lower rate between the weight-rate and Flat Rate Green.

It's also important to note that Flat Rate Green rates are only available to specific ShippingEasy subscription plans: Plus, Select, Premium, Enterprise. Learn more about plan differences. Any ShippingEasy subscriber can access weight-based rates.

Detailed service comparison:

The tables below provide a visual summary of when it's best to enter dimensions for Flat Rate Green or weight-based service, based on weight and zone:

TIP: to simplify the data, we use a color and letter code to indicate the best packaging. Please keep in mind that services listed are only the best value when your products will fit into the defined package dimensions. Use the legend below to read the following charts.
Legend for comparison tables
Priority Mail Service Code Packaging
Flat Rate Green 1 Tier 1, only
2 Tier 1 or 2
3 Tier 1, 2, or 3
4 Tier 1, 2, 3, or 4
5 Tier, 1, 2, 3, 4, or 5
Weight-based W Any package
less than 108" girth
 

Weight-based rates vs all Flat Rate Green Tiers:

Weight-based rates vs all Flat Rate Green Tiers

Prices by Zone: Commercial Plus
Weight
Not Over
(Lbs)
Zones 1 & 2
Local
Zone 3 Zone 4 Zone 5 Zone 6 Zone 7 Zone 8 Zone 9
0.5 W W W W W W W W
1 W W W W W W W W
2 W W W 1 2 2 2 2
3 W W 2 3 3 3 3 3
4 W 1 2 3 3 4 4 4
5 1 1 2 4 5 5 5 5
6 1 2 2 5 5 5 5 5
7 1 2 4 5 5 5 5 5
8 1 2 4 5 5 5 5 5
9 2 2 4 5 5 5 5 5
10 2 3 5 5 5 5 5 5
11 2 4 5 5 5 5 5 5
12 4 4 5 5 5 5 5 5
13 4 4 5 5 5 5 5 5
14 4 5 5 5 5 5 5 5
15 4 5 5 5 5 5 5 5
16 5 5 5 5 5 5 5 5
17 5 5 5 5 5 5 5 5
18 5 5 5 5 5 5 5 5
19 5 5 5 5 5 5 5 5
20 5 5 5 5 5 5 5 5
Take away:

When shipping packages less than 2 lbs, weight-based rates will be the best value. The same applies to packages between 2 lbs and 4 lbs when shipping to closer destinations, Zones 1-4. Also, any packages weighing more than 20 lbs will not qualify for Flat Rate Green.

In many cases, if you ship small packages weighing less than 20 lbs, you'll get a better rate with Flat Rate Green by entering package dimensions.

The greatest advantages come when shipping further, to Zones 5-9. In this case, even Tier 5 shipments (less than 0.5 cubic feet) weighing more than 5 lbs ship for less under Flat Rate Green.

For closer destinations, Zones 1-4, Tier 5 packages do not see an advantage until the 10 lb - 15 lb and above range.

If package dimensions are entered, ShippingEasy will always quote the lower rate between the weight-rate and Flat Rate Green.

Weight-based rates vs Flat Rate Green Tier 1:

Weight-based rates vs Flat Rate Green Tier 1

Prices by Zone: Commercial Plus
Weight
Not Over
(Lbs)
Zones 1 & 2
Local
Zone 3 Zone 4 Zone 5 Zone 6 Zone 7 Zone 8 Zone 9
0.5 W W W W W W W W
1 W W W W W W W W
2 W W W 1 1 1 1 1
3 W W 1 1 1 1 1 1
4 W 1 1 1 1 1 1 1
5
and up
1 1 1 1 1 1 1 1
Take away:

When your products fit into a package that is smaller than 0.1 cubic feet, enter your package dimensions to get the best rate. Learn how to automatically apply dimensions to your shipments.

Packages weighing less than 2 lbs will get the best price through the weight-rate. Those weighing more than 5 lbs will get the best price under Flat Rate Green. Though, any packages weighing more than 20 lbs will not qualify for Flat Rate Green.

Shipments weighing between 2 lbs and 5 lbs will see the best service change based on distance traveled. The advantage shifts from weight-rates to Flat Rate Green with increasing Zone.  Flat Rate Green offers the best price for shipments over 2 lbs destined for Zones 5-9.

If package dimensions are entered, ShippingEasy will always quote the lower rate between the weight-rate and Flat Rate Green.

Weight-based rates vs Flat Rate Green Tier 2:

Weight-based rates vs Flat Rate Green Tier 2

Prices by Zone: Commercial Plus
Weight
Not Over
(Lbs)
Zones 1 & 2
Local
Zone 3 Zone 4 Zone 5 Zone 6 Zone 7 Zone 8 Zone 9
0.5 W W W W W W W W
1 W W W W W W W W
2 W W W W 2 2 2 2
3 W W 2 2 2 2 2 2
4 W W 2 2 2 2 2 2
5 W W 2 2 2 2 2 2
6 W 2 2 2 2 2 2 2
7 W 2 2 2 2 2 2 2
8 W 2 2 2 2 2 2 2
9 2 2 2 2 2 2 2 2
10
and up
2 2 2 2 2 2 2 2
Take away:

When your products fit into a package that is smaller than 0.2 cubic feet, enter your package dimensions to get the best rate. Learn how to automatically apply dimensions to your shipments.

Packages weighing less than 2 lbs will get the best price through the weight-rate. Those weighing more than 9 lbs will get the best price under Flat Rate Green. Though, any packages weighing more than 20 lbs will not qualify for Flat Rate Green.

Shipments weighing between 2 lbs and 9 lbs will see the best service change based on distance traveled. The advantage shifts from weight-rates to Flat Rate Green with increasing Zone.  Flat Rate Green offers the best price for shipments over 3 lbs destined for Zones 4-9.

If package dimensions are entered, ShippingEasy will always quote the lower rate between the weight-rate and Flat Rate Green.

Weight-based rates vs Flat Rate Green Tier 3:

Weight-based rates vs Flat Rate Green Tier 3

Prices by Zone: Commercial Plus
Weight
Not Over
(Lbs)
Zones 1 & 2
Local
Zone 3 Zone 4 Zone 5 Zone 6 Zone 7 Zone 8 Zone 9
0.5 W W W W W W W W
1 W W W W W W W W
2 W W W W W W W W
3 W W W 3 3 3 3 3
4 W W W 3 3 3 3 3
5 W W W 3 3 3 3 3
6 W W W 3 3 3 3 3
7 W W 3 3 3 3 3 3
8 W W 3 3 3 3 3 3
9 W W 3 3 3 3 3 3
10 W 3 3 3 3 3 3 3
11 W 3 3 3 3 3 3 3
12 3 3 3 3 3 3 3 3
13 3 3 3 3 3 3 3 3
14 3 3 3 3 3 3 3 3
15
and up
3 3 3 3 3 3 3 3
Take away:

When your products fit into a package that is smaller than 0.3 cubic feet, enter your package dimensions to get the best rate. Learn how to automatically apply dimensions to your shipments.

Packages weighing less than 3 lbs will get the best price through the weight-rate. Those weighing more than 12 lbs will get the best price under Flat Rate Green. Though, any packages weighing more than 20 lbs will not qualify for Flat Rate Green.

Shipments weighing between 3 lbs and 12 lbs will see the best service change based on distance traveled. The advantage shifts from weight-rates to Flat Rate Green with increasing Zone.  Flat Rate Green offers the best price for shipments over 3 lbs destined for Zones 5-9.

If package dimensions are entered, ShippingEasy will always quote the lower rate between the weight-rate and Flat Rate Green.

Weight-based rates vs Flat Rate Green Tier 4:

Weight-based rates vs Flat Rate Green Tier 4

Prices by Zone: Commercial Plus
Weight
Not Over
(Lbs)
Zones 1 & 2
Local
Zone 3 Zone 4 Zone 5 Zone 6 Zone 7 Zone 8 Zone 9
0.5 W W W W W W W W
1 W W W W W W W W
2 W W W W W W W W
3 W W W W W W W W
4 W W W W W 4 4 4
5 W W W 4 4 4 4 4
6 W W W 4 4 4 4 4
7 W W 4 4 4 4 4 4
8 W W 4 4 4 4 4 4
9 W W 4 4 4 4 4 4
10 W W 4 4 4 4 4 4
11 W 4 4 4 4 4 4 4
12 4 4 4 4 4 4 4 4
13 4 4 4 4 4 4 4 4
14 4 4 4 4 4 4 4 4
15
and up
4 4 4 4 4 4 4 4
Take away:

When your products fit into a package that is smaller than 0.4 cubic feet, enter your package dimensions to get the best rate. Learn how to automatically apply dimensions to your shipments.

Packages weighing less than 4 lbs will get the best price through the weight-rate. Those weighing more than 12 lbs will get the best price under Flat Rate Green. Though, any packages weighing more than 20 lbs will not qualify for Flat Rate Green.

Shipments weighing between 4 lbs and 12 lbs will see the best service change based on distance traveled. The advantage shifts from weight-rates to Flat Rate Green with increasing Zone.  Flat Rate Green offers the best price for shipments over 5 lbs destined for Zones 5-9.

If package dimensions are entered, ShippingEasy will always quote the lower rate between the weight-rate and Flat Rate Green.

Weight-based rates vs Flat Rate Green Tier 5:

Weight-based rates vs Flat Rate Green Tier 5

Prices by Zone: Commercial Plus
Weight
Not Over
(Lbs)
Zones 1 & 2
Local
Zone 3 Zone 4 Zone 5 Zone 6 Zone 7 Zone 8 Zone 9
0.5 W W W W W W W W
1 W W W W W W W W
2 W W W W W W W W
3 W W W W W W W W
4 W W W W W W W W
5 W W W W 5 5 5 5
6 W W W 5 5 5 5 5
7 W W W 5 5 5 5 5
8 W W W 5 5 5 5 5
9 W W W 5 5 5 5 5
10 W W 5 5 5 5 5 5
11 W W 5 5 5 5 5 5
12 W W 5 5 5 5 5 5
13 W W 5 5 5 5 5 5
14 W 5 5 5 5 5 5 5
15 W 5 5 5 5 5 5 5
16 5 5 5 5 5 5 5 5
17 5 5 5 5 5 5 5 5
18 5 5 5 5 5 5 5 5
19 5 5 5 5 5 5 5 5
20 5 5 5 5 5 5 5 5
Take away:

When your products fit into a package that is smaller than 0.5 cubic feet, enter your package dimensions to get the best rate. Learn how to automatically apply dimensions to your shipments.

Packages weighing less than 5 lbs will get the best price through the weight-rate. Those weighing more than 16 lbs will get the best price under Flat Rate Green. Though, any packages weighing more than 20 lbs will not qualify for Flat Rate Green.

Shipments weighing between 5 lbs and 16 lbs will see the best service change based on distance traveled. The advantage shifts from weight-rates to Flat Rate Green with increasing Zone.  Flat Rate Green offers the best price for shipments over 6 lbs destined for Zones 5-9.

If package dimensions are entered, ShippingEasy will always quote the lower rate between the weight-rate and Flat Rate Green.

 

Continue comparing services:

Consider the conclusions that you've drawn about your shipments and whether or not dimensional rates with Flat Rate Green or weight-based rates are the better value. Then use this information to continuing comparing the best of the two with your other Priority Mail service options:

Flat Rate Green (dimensional):

Is Flat Rate Green a good fit for your shipments? If so, take a look at these other rate comparison guides:

Weight-based rates:

Is weight-based a good fit for your shipments? If so, take a look at these other rate comparison guides:

 


Related articles:

Best of Rules: Assign a package and dimensions to my shipments
What is Flat Rate Green and does it relate to cubic pricing?
USPS Priority Mail: Guide to domestic service and package rates
Package Sizes and Dimensions: USPS Domestic
ShippingEasy's USPS Rate Tables

Comments

Please sign in to leave a comment.

Community browse

COMMUNITY FORUMS

Questions & Answers

Issues & Bugs

Beta Feedback

FEATURE REQUESTS

Productivity: Features, Interface & Settings

Partners: Integrations, Carriers & Stores

Shipping: Orders, Labels & Shipments

Inventory: Products, Purchase Orders & Suppliers