The Intelligent Mail barcode is a 65-barcode used to sort and track letters and flats. It allows mailers to use a single barcode to participate in multiple Postal Service programs simultaneously, expands mailers' ability to track individual mailpieces, and provides greater mail stream visibility. 

The IMb is required for use on letters and flats prepared for automation prices. This requirement affects First-Class Mail postcards, Standard Mail, Nonprofit and any other mail using extra services currently available and appropriate for the class and shape of mail prepared for automation prices.

IMB Tracking : One of the benefits of the IMB barcode is the ability to track your mail. IMB Tracking is an additional service that DMR is able to provide for tracking for your letter size mail pieces. After your mail project has mailed, DMR will be able to supply you a report showing what day your mail has been delivered to each recipients.

To summarize, reports show when the mail piece hits the USPS sort machines. Meaning, this is the final scan before it goes onto the mail truck and is indicated to be delivered that day.