Stamps.com is a USPS postage reseller which grants access to all standard services offered by USPS, as well as additional international shipping options through Globalpost. US-based ShipStation users can take advantage of a free Stamps.com account, which will allow you to create domestic and international USPS shipping labels at a discounted rate compared to USPS retail services.
Connection Requirements:
Nothing! ShipStation accounts come with a Stamps.com account already set up so you can get rates right away. You'll be prompted to enter your billing information the first time you create a Stamps.com shipping label.
If you want to connect an additional Stamps.com account to ShipStation, you'll need an active account with Stamps.com. Click here to register for an additional account!
Stamps.com is automatically connected to ShipStation when you sign up for a US-based ShipStation account. Once you set up the billing information for Stamps.com, ShipStation will create a Stamps.com account on you behalf which will be used to create shipping labels. You'll be prompted to add billing information the first time you attempt to create a Stamps.com shipping label, or you can set up the billing information in advance through the Carriers & Fulfillment setting page.
To connect additional Stamps.com accounts to ShipStation, follow the steps below:
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Select the Stamps.com tile and click Connect.
Select the option I already have a Stamps.com account, then enter your Stamps.com Username and Password, and choose an Account Nickname which you'll use to identify the carrier account in ShipStation.
Click Next.
Click Connect.
ShipStation's integration to Stamps.com supports for the following standard features:
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Common ShipStation Features
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Note
* If you have Parcel Select Lightweight enabled, selecting Parcel Select Ground and Package for anything under 16 oz will automatically print a Parcel Select Lightweight label.
Contact Stamps.com shipper support to enable it on your ShipStation account (subject to USPS approval). Additional fees and guidelines from the postage provider may apply.
To learn more about USPS Shipping services, see USPS Domestic Services and USPS International Service pages.
Additional Features
ShipStation's integration to Stamps.com allows for the following additional features:
Feature |
Description |
|---|---|
Discounted Rates |
The free Stamps.com account included with ShipStation comes pre-loaded with access to discounted rates, including cubic pricing! NoteYou'll only have access to these rates when using the free Stamps.com account. If you connected a personal Stamps.com account, ShipStation will instead reflect whatever rates are loaded into that account. |
GlobalPost Consolidation Service |
The free Stamps.com account included with ShipStation qualifies for GlobalPost consolidation services through Stamps.com. See our section on GlobalPost for more information. |
Scheduled Pickups |
After creating Stamps.com shipping labels in ShipStation, you can schedule a pickup for the next day through the Shipping tab. |
Manage funds through ShipStation |
You can add funds to your Stamps.com account through ShipStation, using the credit card you have on file with Stamps.com. You can also set up auto-funding so you always have funds available to create shipping labels. |
USPS SCAN Forms |
You can use ShipStation to generate USPS SCAN forms for your Stamps.com shipping labels. |
Stamps.com cubic pricing is available by default for all ShipStation users creating labels in ShipStation with their Stamps.com account.
Cubic rates are ideal for small, heavy packages since the pricing is based on the volume of the package instead of the weight. Any package that measures 0.50 cubic feet or less and is 20 pounds or less is eligible.
To receive cubic rates in ShipStation:
Choose a USPS domestic Priority service.
Choose a package type of Package.
Enter the package weight & dimensions.
ShipStation will automatically apply the Cubic rate whenever it's cheaper than the Priority rate. For more details on Stamps.com cubic rates, please contact your Stamps.com account representative.
USPS offers a special cubic rate option for a package type called Softpack or Polybag. These package types are not yet available in ShipStation, but we plan to make them available in the future.
The following steps will allow you to view the appropriate cubic rate for Softpack / Polybag shipments.
To qualify for softpack pricing:
The mailpiece must be 20 lbs or less.
The longest dimension cannot exceed 18 inches.
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Must be .50 cubic feet or less. The following list provides Length + Width for each tier of Cubic Softpack Pricing:
0.1 - Length + Width between 0" and 21"
0.2 - Length + Width between 21" and 27"
0.3 - Length + Width between 27" and 31"
0.4 - Length + Width between 31" and 34"
0.5 - Length + Width between 34" and 36"
May not be in rolls or tubes.
To view the appropriate rates:
Select your order from the Orders grid and choose USPS Priority Mail as the shipping service.
Set packaging type to Large Envelope or Flat.
Enter the weight of the shipment.
Enter the length and width but leave the height field blank.
This will fetch the tiered cubic rate for the product should it meet the requirements for cubic rates.
Stamps.com's GlobalPost services offer you a very economical way to ship international packages that weigh less than 4.4 pounds. Through simplified service options, the shipping costs are greatly-lowered. For more information, read the Stamps.com page about the benefits of using GlobalPost.
The free Stamps.com account provided to all ShipStation users is eligible for GlobalPost. Contact Stamps.com at ShipperSupport@Stamps.com to enroll in the GlobalPost program. If you expect that you'll be shipping more than 10 GlobalPost shipments per day, you'll also want to inquire about GlobalPost SmartSaver shipping options.
After you've been approved for GlobalPost services, you can enable them for use in ShipStation by doing the following:
Select or create an international order.
Choose an existing Stamps.com international service.
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Click Create Label to bring up the cost summary screen.
Note
If you use QuickShip, disable it for this step. You must see the Cost Summary screen to add the GlobalPost services.
Once the above steps have been completed, the GlobalPost services will be available alongside your other Stamps.com international shipping services.
Review the GlobalPost services listed below for details such as the available package types and maximum weights.
Table 5. GlobalPost Economy Int'l
Available Package Types |
Max Weight |
Min Dimensions |
Max Dimensions |
|---|---|---|---|
Large Envelope or Flat |
13 oz |
11.5" x 6.125"x 0.25" |
15" x 12" x 0.75" |
Package, Thick Envelope |
16 oz |
5" x 3.5" x 0.75" |
Max length (the longest side): 24" Length + Width + Height cannot exceed 36" |
Rolls |
16 oz |
Min length (the longest side) is 4". Minimum length + 2x Diameter is 6 - 3/4" |
Max Length (i.e. the longest side) is 36" Max Length + 2x Diameter cannot exceed 42" |
Table 6. GlobalPost Standard Int'l
Available Package Types |
Max Weight |
Min Dimension |
Max Dimension |
|---|---|---|---|
Large Envelope or Flat |
17.6 oz |
11.5" x 6.125" x 0.25" |
15" x 12" 0.75" |
Package, Thick Envelope |
70 oz |
5" x 3.5" x 0.75" |
Max Length (i.e. the longest side) is 24" Length + Width + Height cannot exceed 36" |
Flat Rate Envelope, Flat Rate Padded Envelope, Flat Rate Legal Envelope, Small Flat Rate Box |
64 oz |
Based on Flat Rate package type |
Based on Flat Rate package type |
Rolls |
70 oz |
Min Length (i.e. the longest side) is 4" Minimum Length + 2x Diameter is 6-3/4" |
Max Length (i.e. the longest side) is 36" Max Length + 2x Diameter cannot exceed 42" |
Table 7. GlobalPost Smartsaver Economy Intl, GlobalPost Smartsaver Standard Intl
Available Package Types |
Max Weight |
Min Dimension |
Max Dimension |
|---|---|---|---|
Large Envelope or Flat |
17.6 oz |
11.5" x 6.125" x 0.25" |
15" x 12" x 0.75" |
Package, Thick Envelope |
70 oz |
6" x 4" x 0.75" |
Max Length (i.e. the longest side) is 24" Length + Width + Height cannot exceed 36" Max Length (i.e. the longest side) is 24" Length + Width + Height cannot exceed 36" |
Rolls |
70 oz |
Min Length (i.e. the longest side) is 4" Minimum Length + 2x Diameter is 6-3/4" |
Max Length (i.e. the longest side) is 36" Max Length + 2x Diameter cannot exceed 42" |
Here's some things you should keep in mind when using Stamps.com GlobalPost services in ShipStation:
To use the "Rolls" package type in ShipStation: Select the standard "Package" option. Do not include dimensions for Rolls package type, use the weight only.
GlobalPost shipments are prepaid, and GlobalPost shares funds with your Stamps.com account.
All GlobalPost shipments include $100 of standard coverage. Additional Carrier Insurance is not available for GlobalPost shipments. Shipsurance is available, with a maximum declared value of $400.
GlobalPost Economy International and GlobalPost Standard International shipments can be included on USPS SCAN forms. GlobalPost SmartSaver shipments should not be included in USPS SCAN forms.
The label that you'll print from ShipStation will be a domestic USPS shipping label. This label is used to ship your package to a GlobalPost sorting facility, where GlobalPost will relabel the package with any necessary documents for international shipping.
No customs forms will be printed from ShipStation. Instead, ShipStation will submit the customs information electronically and GlobalPost will include any necessary customs documents when the package is relabeled at their sorting facility.
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There are two tracking numbers associated with a GlobalPost shipment:
The GlobalPost tracking number. This tracking number is sent to your customer or selling channel during ShipStation's notification processes. For Economy shipments, packages are tracked only to the GlobalPost sorting facility. For Standard and Smartsaver shipments, packages are tracked to the destination address.
The tracking number on the actual label generated in ShipStation. This tracking number can only be used to track the movement from your Ship From Location to the GlobalPost sorting facility. It is not shared with your customer or selling channel.
GlobalPost SmartSaver
GlobalPost SmartSaver services are available for accounts that ship more than 10 packages per day with GlobalPost.
GlobalPost SmartSaver works much like other GlobalPost services, but instead of sending each package individually, you bundle all the shipments into a larger package and ship the larger package to the GlobalPost sorting facility via UPS or FedEx.
Here is the SmartSaver process:
Create GlobalPost SmartSaver shipping labels for all the shipments and package them as you would any other shipment.
Instead of shipping the packages individually, put all the SmartSaver shipments into a single larger package.
Create a manual order in ShipStation destined for the GlobalPost sorting facility, using the weight and dimensions for the larger package containing the SmartSaver shipments.
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Select UPS Ground or FedEx Ground as the shipping services (based on your agreement with GlobalPost) and assign Third Party Billing information to the shipment. GlobalPost will provide you with the required Third Party Billing information.
Tip
This step can be automated with Automation Rules. The easiest way to do that is to create a manual store specifically for the consolidation orders, then use the manual store as criteria for an automation rule that assigns the service and Third Party Billing information.
Create the label and apply to the larger package and hand over to the carrier (either UPS or Fedex).
When the GlobalPost sorting facility receives the shipment, they'll remove the individual packages and relabel them as needed, then send them on their way to the final destination.
Here are some things you should keep in mind about ShipStation's integration with Stamps.com:
USPS does not support Signature or Adult Signature confirmation for shipments to international addresses.
USPS SCAN forms must be created before 9 PM local time.
Label Messages are not available for international shipments, or domestic First Class Mail shipments using the Letter package type.
Due to the discounted rates received by ShipStation users, it's not possible to show postage cost on Stamps.com shipping labels.
All Stamps.com shipping label are prepaid. In order to receive a refund for unused postage, you can void the shipping label electronically within 28 days.
Stamps.com has a postage purchase minimum of $10 for a single transaction.
Each Stamps.com account can hold up to a maximum of $10,000.00 in available funds.
Here are some common issues, potential causes, and available troubleshooting tips.
Issue |
How to troubleshoot or resolve |
|---|---|
Why aren't my First Class Mail International (FCMI) shipments' tracking numbers being sent to my customers or selling channel? |
The tracking number provided for FCMI shipments is not always fully trackable, and will often not provide any additional tracking details beyond the shipment leaving the country. Since these tracking numbers do not always provide full delivery information, ShipStation considers them to be non-trackable tracking numbers and will not include them in notifications by default. If you want ShipStation to include FCMI tracking numbers in notifications, go to |
Why am I getting the error "Authentication Failed" when attempting to get rates or create shipping labels? |
This error message will occur if you've updated the password for your Stamps.com account. It means that ShipStation no longer has the proper password for your account and is unable to communicate successfully with Stamps.com. To resolve this error, go to If you are still unable to use your Stamps.com account, contact Stamps Shipper support at (877) 782-6739 (Option 1) for further assistance. |
My Priority Mail Express shipment arrived late, how do I get a refund for the late delivery? |
You will need to contact Stamps.com directly to claim a refund for late delivery. Email shippersupport@stamps.com with the tracking number(s) and created date(s) for the shipment(s). Stamps.com will evaluate the claim and respond within 24 hours. |
I created a shipment using the First Class Mail International (FCMI) service and the Large Envelope or Flat package type but got a domestic shipping label. What should I do? |
Starting in early 2018, USPS requires all "Merchandise" shipped using FCMI to use the Package package type. The Large Envelope or Flat package type is only valid if the content type for the shipment is "Documents." Stamps.com allows their users to use the Large Envelope or Flat package type for any kind of FCMI shipment, but in order to do so the shipment must go through GlobalPost, an international consolidation service. The domestic shipping label you received is used to ship your package to the GlobalPost sorting facility. Once received, GlobalPost will relabel the shipment with a new label and any necessary customs information, and send the package on it's way to it's final destination. See our section on GlobalPost for more details. |
Error Account is set to a closed plan |
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USPS rates increased on January 27th, 2019. All USPS postage providers, including Stamps.com, must comply with these new rate increases. Listed below are some of the more common services that will see rate increases.
Below you'll find the Stamps.com 2019 rate tables for:
First Class Mail Packages
Priority Flat Rate
Priority Regional Rate Boxes
Priority Mail
Any size restrictions will also be listed in each section.
First Class Package Services: Previously, First Class Packages had a flat rate to all zones. In 2019, FCP services will be based on both weight and zone. Zones range from the nearest (zone 1) to the furthest away (zone 9).
No more balloon pricing: Previously, the USPS charged lightweight Priority Mail and Parcel Select packages with a girth between 84" and 108" a rate based on a 20 lb weight. This has been discontinued.
Dimensional weight: Priority Mail over one cubic foot will be subject to dimensional weight (AKA: DIM weight) starting June 23, 2019. Details in the Priority Mail section below.
In order to conform to the USPS pricing policy changes for dimensional weight and international shipments, Stamps.com will make the following changes, effective June 23rd, 2019:
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The Large Package package type will represent any package over the default dimensional weight threshold of one cubic foot.
Dimensions will be required if you use the Large Package package type with the Priority Mail, Priority Mail Express, or Parcel Select Ground shipping services.
The Package package type will represent any packages that are one cubic foot or less, and will not require dimensions in ShipStation.
When calculating dimensional weight, the weight divisor will be lowered to 166. The new formula to determine dimensional weight will be (Length x Width x Height) / 166.
The maximum weight for a USPS First Class International shipment that uses the Large Envelope or Flats package type with a Contents type of Documents will be lowered to 15.994 oz.
The maximum weight for a USPS First Class International shipment that uses the Large Envelope or Flats package type with a Contents type other than Documents will be increased to 4.4 lbs, as part of Stamps.com's Global Advantage Program.
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 |
$2.66 |
$2.68 |
$2.70 |
$2.76 |
$2.84 |
$2.96 |
$3.09 |
$3.09 |
2 |
$2.66 |
$2.68 |
$2.70 |
$2.76 |
$2.84 |
$2.96 |
$3.09 |
$3.09 |
3 |
$2.66 |
$2.68 |
$2.70 |
$2.76 |
$2.84 |
$2.96 |
$3.09 |
$3.09 |
4 |
$2.66 |
$2.68 |
$2.70 |
$2.76 |
$2.84 |
$2.96 |
$3.09 |
$3.09 |
5 |
$3.18 |
$3.20 |
$3.22 |
$3.28 |
$3.36 |
$3.49 |
$3.63 |
$3.63 |
6 |
$3.18 |
$3.20 |
$3.22 |
$3.28 |
$3.36 |
$3.49 |
$3.63 |
$3.63 |
7 |
$3.18 |
$3.20 |
$3.22 |
$3.28 |
$3.36 |
$3.49 |
$3.63 |
$3.63 |
8 |
$3.18 |
$3.20 |
$3.22 |
$3.28 |
$3.36 |
$3.49 |
$3.63 |
$3.63 |
9 |
$3.82 |
$3.85 |
$3.88 |
$3.96 |
$4.06 |
$4.19 |
$4.33 |
$4.33 |
10 |
$3.82 |
$3.85 |
$3.88 |
$3.96 |
$4.06 |
$4.19 |
$4.33 |
$4.33 |
11 |
$3.82 |
$3.85 |
$3.88 |
$3.96 |
$4.06 |
$4.19 |
$4.33 |
$4.33 |
12 |
$3.82 |
$3.85 |
$3.88 |
$3.96 |
$4.06 |
$4.19 |
$4.33 |
$4.33 |
13 |
$4.94 |
$4.98 |
$5.02 |
$5.12 |
$5.24 |
$5.38 |
$5.53 |
$5.53 |
14 |
$4.94 |
$4.98 |
$5.02 |
$5.12 |
$5.24 |
$5.38 |
$5.53 |
$5.53 |
15 |
$4.94 |
$4.98 |
$5.02 |
$5.12 |
$5.24 |
$5.38 |
$5.53 |
$5.53 |
15.99 |
$4.94 |
$4.98 |
$5.02 |
$5.12 |
$5.24 |
$5.38 |
$5.53 |
$5.53 |
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 |
$6.95 |
Legal Flat Rate Envelope |
$7.25 |
Padded Flat Rate Envelope |
$7.55 |
Small Flat Rate Box |
$7.50 |
Medium Flat Rate Boxes |
$12.80 |
Large Flat Rate Box |
$17.60 |
APO/FPO/DPO Large FRB |
$16.10 |
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 |
$7.60 |
$7.80 |
$8.07 |
$8.71 |
$9.95 |
$10.50 |
$11.15 |
$15.59 |
Regional Rate Box B |
$8.00 |
$8.45 |
$9.35 |
$10.60 |
$16.10 |
$18.42 |
$20.98 |
$29.68 |
To view zones relative to your ship from location, use the USPS Domestic Zone Chart tool.
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 |
$6.95 |
$7.28 |
$7.49 |
$7.65 |
$7.82 |
$7.99 |
$8.25 |
$9.91 |
2 |
$7.42 |
$7.61 |
$7.88 |
$8.50 |
$9.70 |
$10.23 |
$10.86 |
$15.17 |
3 |
$7.61 |
$7.99 |
$8.34 |
$9.26 |
$11.80 |
$13.10 |
$15.28 |
$20.58 |
4 |
$7.71 |
$8.20 |
$8.81 |
$10.03 |
$13.75 |
$15.59 |
$17.61 |
$24.75 |
5 |
$7.81 |
$8.25 |
$9.12 |
$10.33 |
$15.67 |
$17.92 |
$20.40 |
$28.84 |
6 |
$7.91 |
$8.29 |
$9.22 |
$13.77 |
$17.93 |
$20.83 |
$23.81 |
$33.05 |
7 |
$8.15 |
$9.41 |
$9.46 |
$15.43 |
$19.86 |
$23.48 |
$26.75 |
$37.11 |
8 |
$8.20 |
$9.87 |
$11.16 |
$16.84 |
$21.82 |
$25.85 |
$30.04 |
$41.66 |
9 |
$9.01 |
$10.25 |
$11.62 |
$18.06 |
$23.74 |
$28.00 |
$33.40 |
$46.33 |
10 |
$9.38 |
$10.67 |
$11.69 |
$19.51 |
$25.64 |
$30.79 |
$36.32 |
$50.38 |
11 |
$10.67 |
$12.77 |
$13.69 |
$21.31 |
$27.52 |
$33.51 |
$39.34 |
$55.04 |
12 |
$11.32 |
$13.58 |
$15.93 |
$22.81 |
$30.01 |
$36.23 |
$42.20 |
$59.01 |
13 |
$11.91 |
$14.36 |
$16.68 |
$24.03 |
$32.21 |
$37.69 |
$43.69 |
$61.12 |
14 |
$12.52 |
$15.15 |
$17.57 |
$25.43 |
$34.02 |
$39.79 |
$45.86 |
$64.15 |
15 |
$13.01 |
$15.94 |
$18.42 |
$26.74 |
$35.33 |
$40.56 |
$47.06 |
$65.84 |
16 |
$13.45 |
$16.79 |
$19.42 |
$28.07 |
$37.34 |
$42.84 |
$49.52 |
$69.46 |
17 |
$13.88 |
$17.57 |
$20.35 |
$29.44 |
$39.23 |
$45.07 |
$52.29 |
$73.12 |
18 |
$14.15 |
$18.11 |
$21.26 |
$30.76 |
$41.31 |
$47.29 |
$54.91 |
$76.81 |
19 |
$14.48 |
$18.53 |
$21.75 |
$31.57 |
$43.16 |
$49.49 |
$57.51 |
$80.45 |
20 |
$15.05 |
$18.82 |
$22.19 |
$32.15 |
$44.28 |
$51.34 |
$60.18 |
$84.16 |
21 |
$15.71 |
$19.27 |
$22.70 |
$32.72 |
$44.63 |
$51.82 |
$60.95 |
$85.93 |
22 |
$16.21 |
$19.79 |
$23.46 |
$33.37 |
$44.93 |
$52.22 |
$61.65 |
$86.96 |
23 |
$16.69 |
$20.26 |
$24.02 |
$33.98 |
$45.18 |
$52.58 |
$62.02 |
$87.47 |
24 |
$17.37 |
$20.26 |
$24.02 |
$33.98 |
$45.18 |
$52.58 |
$62.02 |
$87.47 |
25 |
$18.04 |
$21.87 |
$26.99 |
$36.50 |
$46.81 |
$55.30 |
$64.64 |
$91.15 |
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 Mail parcels in all shipping zones will use DIM pricing for packages over 1 cubic foot starting January 27th, 2019. Previously, only Priority Mail parcels being delivered to Zones 5-9 received DIM pricing.
Additionally, DIM pricing for all zones will also apply to Priority Mail Express and Parcel Select Ground parcels larger than one cubic foot.
To determine if your package is larger than one cubic foot, use this equation: (L x W x H) / 1728. If the result is greater than 1, the package will be subject to dimensional weight.
You can calculate dimensional weight using this equation: (L x W x H) / DIM Divisor.
The DIM Divisor will change from 194 to 166 on 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 always entering the correct package dimensions when configuring your shipments so the rate you see in ShipStation reflects 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, which can automatically deduct the difference in postage from your USPS postage provider account.
Tip
To see more details on the increases from 2018 to 2019 - including Priority Mail Express and Media Mail options - please review the very thorough blog post from Stamps.com: New USPS Postage Rates for 2019.