General FAQs

Tracking USPS First Class letters with IMB on ShipBlink and EasyPost

USPS First Class letters are an affordable way to send mail across the United States. However, tracking these letters can be a bit challenging. Fortunately, with the Intelligent Mail Barcode (IMB) technology, tracking USPS First Class letters is now possible, and ShipBlink and EasyPost are two platforms that offer this service.

IMB technology enables USPS to track a letter or package at every point in the delivery process. The barcode contains information such as the sender’s address, recipient’s address, and the delivery confirmation number. This information is updated in real-time and can be accessed by the sender or receiver.

The tracking available for USPS First Class letters is known as IMB (Intelligent Mail Barcode) tracing. While it doesn’t update for every step of the way like package tracking, it lets you know if a First Class Letter or Flat has been delivered. The EasyPost tracking page will have the information for the USPS labels generated through EasyPost.

The idea behind passing the “Delivery Confirmation” field in Shipping Options for these letters is so that receiver has to confirm reception with a signature. It shouldn’t matter the signature value provided, as the list below should be available for your USPS shipments via EasyPost.

delivery_confirmation
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If you want to request a signature, you can pass “ADULT_SIGNATURE” or “SIGNATURE”. You may also request “NO_SIGNATURE” to leave the package at the door. • All – some options may be limited for international shipments • FedEx – “INDIRECT_SIGNATURE” is also an option • USPS – additional options ◦ “ADULT_SIGNATURE_RESTRICTED” ◦ “SIGNATURE_RESTRICTED” • Canada Post – “DO_NOT_SAFE_DROP”