About DSF2 Processing

The United States Postal Service® DSF2 electronic database, containing every deliverable address in the country, helps keep mailing lists current by identifying deliverable addresses and specific address attributes. With more than 135 million addresses currently on file, it is the most complete address database available, and offers detail that allows validation for both correctness and completeness of addresses. If records cannot be matched with DSF2, they are probably undeliverable. DSF2 can also be used to obtain walk-sequence codes.

Classification Reform created a new postage rate level called Enhanced Carrier Route (ECR). Mailers claiming the new ECR Basic, High Density or Saturation discounts must present mail in either enhanced Line of Travel or Walk Sequence. Mailers can have walk sequence codes assigned to their database through BCC Data Services. Address records with walk sequence codes can be sorted into Walk Sequence during the presort process using Mail Manager 2010.