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Merchant Onboarding and Authorization Tech Guide
Merchants need to follow a two-step process to authorize a Label Provider to generate shipping labels on their behalf.
1. Log in or create a USPS business account on the Customer Onboarding Portal (COP) to get Customer Registration ID (CRID), Mailer ID (MID), and Enterprise Payment Account (EPA). A CRID is a unique identifier for your company. A MID is another identifier which can be part of the barcode on a piece of mail.
2. Authorize Label Provider in COP. Before the merchant’s account can be used by Label Provider, Label Provider must be authorized. This will also enable Label Provider to generate package labels on behalf of NSA Holders at their NSA rates.
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