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USPS Rates in ShipStation

The USPS rates available in ShipStation will reflect the rates available to your connected postage provider accounts (Stamps.com, Endicia, Express1), including any negotiated rates enabled for that account.

By default, ShipStation users with a Stamps.com account have access to discounted USPS pricing corresponding with Commercial Base pricing. These rates will automatically apply to shipments when using any Stamps.com service valid for the shipment. This article provides further details on rates and how they apply in ShipStation.

Dimensional Weight (DIM)

Calculate dimensional weight using this equation: (L x W x H) / DIM Divisor.

  • The DIM Divisor changed from 194 to 166 as of June 23, 2019.

If DIM weight applies to your package, the carrier will compare the DIM weight and actual weight and charge the higher of the two for the label. For this reason, ShipStation recommends that you always enter the correct package dimensions when you configure your shipments. Thus, the rate you see in ShipStation will reflect the correct weight.

If the label you print for your shipment reflects the incorrect rate as determined by USPS, you may be subject to the USPS Automated Package Verification. This can automatically deduct the difference in postage from your USPS postage provider account.

Types of USPS Rates

The USPS uses a tiered-rate system. This table outlines each rating tier, and what it means.

Rate Tier

Definition

Retail

The non-discounted rate you pay in person at the post office.

Commercial Base Pricing (CBP)

Online rates through USPS.com (slightly discounted from retail)

Commercial Plus Pricing (CPP)

Highly-discounted rates available to high-volume shippers (must meet a minimum annual shipment threshold)

Cubic Pricing

Highly-discounted rates for high-volume shippers for packages under 20lbs that are no larger than .5 cubic feet (must meet a minimum annual shipment threshold)

Negotiated Rates

If you have a negotiated service contract with your USPS postage provider (Stamps.com, Endicia, etc), these rates will automatically be available in ShipStation.

Stamps.com Rates in ShipStation

Through ShipStation’s relationship with Stamps.com, you automatically have access to the following rates in ShipStation:

Commercial Base Pricing (CBP) rates for these services:

  • Domestic: First Class Package Service, Priority Mail and Priority Mail Express (flat rate and weight-based services)

  • International: Priority Mail International, Priority Mail Express International, and First Class Mail International Package Service

Additionally, Regional Rate Boxes receive preferred ShipStation rates, and are slightly discounted from the CBP Regional Rate Box rate.

For more information on other discounts your account might be eligible for, please contact your Stamps.com account manager.

Review each Rates sections below rate information on specific service classes.

Priority Mail Packages/Thick Envelope

Priority Mail package or thick envelopes are a great way to quickly, yet efficiently, ship packages that are under 70 lbs and do not exceed 108" in combined Length and girth (girth = the distance around its thickest part).

For packages weighing between 11 lbs. and 70 lbs., all shipping zones are seeing lower rates compared to 2018. Cost savings range from $0.11 (11 lbs. Zone 1/2 = $10.67) to $1.37 savings (70 lbs. Zone 8 = $184.51) compared to 2018.

This table lists Priority Mail pricing up to 25lbs for all 9 zones.

  Weight (lb)

Zone

1 & 2

3

4

5

6

7

8

9

1

$7.02

$7.35

$7.56

$7.80

$7.98

$8.15

$8.42

$11.40

2

$7.64

$7.84

$8.12

$8.76

$9.99

$10.54

$11.19

$17.45

3

$7.84

$8.23

$8.59

$9.54

$12.15

$13.49

$15.74

$23.67

4

$7.94

$8.45

$9.07

$10.33

$14.16

$16.06

$18.14

$28.50

5

$8.04

$8.50

$9.39

$10.64

$16.14

$18.46

$21.01

$33.17

6

$8.15

$8.54

$9.50

$14.18

$18.47

$21.45

$24.52

$38.01

7

$8.39

$9.69

$9.74

$15.89

$20.46

$24.18

$27.55

$42.68

8

$8.45

$10.17

$11.49

$17.35

$22.47

$26.63

$30.94

$47.91

9

$9.28

$10.56

$11.97

$18.60

$24.45

$28.84

$34.40

$53.28

10

$9.76

$11.10

$12.16

$20.30

$26.67

$32.03

$37.78

$57.94

11

$11.30

$13.53

$14.50

$22.57

$29.15

$35.50

$41.67

$63.30

12

$12.00

$14.39

$16.89

$24.18

$31.81

$38.40

$44.73

$67.86

13

$12.62

$15.22

$17.68

$25.47

$34.14

$39.95

$46.31

$70.29

14

$13.27

$16.06

$18.62

$26.96

$36.06

$42.18

$48.61

$73.77

15

$13.79

$16.90

$19.53

$28.34

$37.45

$42.99

$49.88

$75.72

16

$14.39

$17.97

$20.78

$30.03

$39.95

$45.84

$53.13

$79.88

17

$14.85

$18.80

$21.77

$31.50

$41.98

$48.22

$55.95

$84.09

18

$15.14

$19.38

$22.75

$32.91

$44.20

$50.60

$58.75

$88.33

19

$15.49

$19.83

$23.27

$33.78

$46.18

$52.95

$61.54

$92.52

20

$16.10

$20.14

$23.74

$34.40

$47.38

$54.93

$64.39

$96.78

21

$16.81

$20.62

$24.29

$35.01

$47.75

$55.45

$65.22

$98.85

22

$17.34

$21.18

$25.10

$35.71

$48.08

$55.88

$65.97

$100.00

23

$17.86

$21.68

$25.70

$36.36

$48.34

$56.26

$66.36

$100.59

24

$18.59

$22.60

$27.16

$37.79

$49.36

$57.73

$67.98

$103.05

25

$19.30

$23.40

$28.88

$39.06

$50.09

$59.17

$69.16

$104.82

For Priority Mail pricing from 25lbs - 70lbs, or information on cubic pricing for packages under 20lbs and 0.5 cubic feet, please contact your Stamps.com account representative directly.

Priority Flat Rate

Priority Mail Flat Rate is a 1-3 day shipping service that charges one flat rate for your package/envelope, with a maximum allowable weight of 70 lbs. 

Flat Rate Packaging

2019 Rates

Flat Rate Envelopes 12-1/2" x 9-1/2" or smaller

$7.15

Legal Flat Rate Envelope

$7.45

Padded Flat Rate Envelope

$7.75

Small Flat Rate Box

$7.65

Medium Flat Rate Boxes

$13.20

Large Flat Rate Box

$18.30

APO/FPO/DPO Large FRB

$16.80

Priority Regional Rate Boxes

Priority Regional Rate Boxes have a zone-dependent flat rate. Depending on the zone you are shipping to, you may find the Regional Rate Box is cheaper. Essentially, Flat Rate Boxes are ideal for shipping long distances and Regional Rate Boxes are ideal for shorter distances.

Below are the costs of sending Regional Rate Boxes to each of the USPS's 9 zones. 

Regional Rate Box A: 10" x 7" x 4.75"

Regional Rate Box B: 12" x 10.25" x 5"

Regional Rate Box

Zone 

1 & 2

3

4

5

6

7

8

9

Regional Rate Box A

$7.63

$7.87

$8.16

$8.87

$10.37

$11.08

$12.05

$18.64

Regional Rate Box B

$8.02

$8.46

$9.37

$11.48

$16.67

$19.16

$21.84

$34.33

To view zones relative to your ship from location, use the USPS Domestic Zone Chart tool. 

First Class Mail Package

If your package weighs less than 16oz and does not exceed 108" in combined length and girth (the measurement around the package at its thickest part), it qualifies for First Class Mail.

First Class Mail is now based on both weight and zone.

Weight (in Ounces)

Zone 1 & 2

Zone 3

Zone 4

Zone 5

Zone 6

Zone 7

Zone 8

Zone 9

1  

$2.74

$2.76

$2.78

$2.84

$2.93

$3.05

$3.18

$3.18

2  

$2.74

$2.76

$2.78

$2.84

$2.93

$3.05

$3.18

$3.18

3  

$2.74

$2.76

$2.78

$2.84

$2.93

$3.05

$3.18

$3.18

4  

$2.74

$2.76

$2.78

$2.84

$2.93

$3.05

$3.18

$3.18

5  

$3.21

$3.23

$3.25

$3.31

$3.39

$3.52

$3.67

$3.67

6  

$3.21

$3.23

$3.25

$3.31

$3.39

$3.52

$3.67

$3.67

7  

$3.21

$3.23

$3.25

$3.31

$3.39

$3.52

$3.67

$3.67

8  

$3.21

$3.23

$3.25

$3.31

$3.39

$3.52

$3.67

$3.67

9  

$3.93

$3.97

$4.00

$4.08

$4.18

$4.32

$4.46

$4.46

10  

$3.93

$3.97

$4.00

$4.08

$4.18

$4.32

$4.46

$4.46

11  

$3.93

$3.97

$4.00

$4.08

$4.18

$4.32

$4.46

$4.46

12  

$3.93

$3.97

$4.00

$4.08

$4.18

$4.32

$4.46

$4.46

13  

$5.04

$5.08

$5.12

$5.22

$5.40

$5.54

$5.70

$5.70

14  

$5.04

$5.08

$5.12

$5.22

$5.40

$5.54

$5.70

$5.70

15  

$5.04

$5.08

$5.12

$5.22

$5.40

$5.54

$5.70

$5.70

15.99  

$5.04

$5.08

$5.12

$5.22

$5.40

$5.54

$5.70

$5.70

Other USPS Postage Providers

Other USPS postage providers, like Endicia and Express1, will offer access to CBP rates, as well as an option for negotiated rate contracts. To find out what rates are available for which services from these postage providers, please reach out to them directly.

The rates available through your postage provider accounts will automatically be available to you in ShipStation!

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