How to Create a USPS Account and Integrate With Shopify 

If you’re running a Shopify store and want to use USPS for shipping, you’ll need to create a USPS business account and gather key credentials like your CRID and MID. In this guide, we’ll walk you through the steps to create a USPS account and integrate it with your Shopify store using the correct credentials, ensuring smooth label generation and accurate rate calculation.

Create a USPS Account 

Follow the steps below to create a USPS Account and obtain the required account details for integration with the PH Multi-Carrier Shipping Label App.

1. Go to the USPS Developer Portal and click on the Getting Started tab.

2. Go to the USPS Customer Onboarding Portal (COP) as shown in the image.

3. Click Create New Account to start the registration process. (If you already have an account, simply sign in to retrieve your credentials.)

4. Enter your email address and submit. USPS will send a verification link; click it to verify your email.

5. In the registration steps:

Step 1: Enter your company information, including address/ ZIP code/ company identifier.  In this example, we have entered the address. Then, click Search Address.

When your address appears, click Confirm Address.

Step 2: Add your contact details to verify your account.

Step 3: Set your username, password, and security questions answers, and create an account.

6. Read through and accept to Terms and Conditions by checking the box, then click Continue.

Once your account is created, you’ll be redirected to a page displaying your,  

• Customer Registration ID (CRID): A USPS-generated identifier for your business location. It connects your shipping activity to your USPS profile.
• Mailer Identifier (MID): A numeric code (6 or 9 digits) assigned by USPS to identify your business for outbound mail tracking.
• Return MID: A specific MID used to manage return shipments, ensuring returns are properly tracked in USPS systems.

(Existing account holders can visit this site to access these credentials.)

Add Payment Details for Your USPS Account

On the same page, you’ll see an option to add a payment method. Agree to the terms and conditions, select your payment account type, and click Continue.

Enter your bank account details and submit.

You will then see your EPS Payment Account Number.

Create an App for API Access

1. Log in to the USPS Developer Portal again. Go to the Apps section from the top menu.

2. Click on Add App to add a Shopify app, such as the PH Multi-Carrier Shipping Label App. 

3. Fill in the app details and click on Add App. 

(We recommend using PH Multi-Carrier Shipping Label as the app name for the PH Multi-Carrier Shipping Label App)

4. Once the app is created, click on the app to get the Consumer Key (client_id) and Consumer Secret (client_secret) under the View tab, as shown in the image.

These credentials will be required in the next step to generate an OAuth token and access protected USPS account information.

Authorize App to Access Protected Information Resources

In the USPS Customer Onboarding Portal, enter your Consumer Key and submit to authorize your app.

This step enables access to your payment accounts, permits, CRIDs, and MIDs required for successful integration.

Now, to get the Manifest MID, go to My Account and click on Manage Locations.

Here, you will be able to get your Manifest/ Master MID as shown in the image.

Integrate Your USPS Account in Shopify 

Now that you have all the required details – CRID, Consumer Key, Consumer Secret, Account Number, MID, Manifest MID, and Return MID- you can seamlessly integrate your USPS account in Shopify with the PH Multi-Carrier Shipping Label App.

Make sure the PH Multi-Carrier Shipping Label App has been installed. 

Add the USPS carrier by selecting USPS Ship. Then, click the Add Account button. 

Now simply copy the credentials you obtained from the previous steps and paste them into their respective fields in the app, then click Connect. 

You’re now successfully connected! 

You can start accessing live rates, generating labels, tracking shipments, and fulfilling orders. Refer to this guide for step-by-step instructions: Setting Up Shopify Multi-Carrier Shipping Label App

Having Trouble?

If you face issues like authentication errors or connection failures, please double-check that all credentials are entered correctly and match the values shown in your USPS portals.

If the issue persists, contact PluginHive support. To expedite resolution or escalate the issue to USPS if required, be sure to include your USPS Account Number in your message.