How to use differential weighing on the DM300C, DM400C, and more

Products affected: DM300C™, DM400C™, DM450C™, DM475™
Differential weighing speeds up the weighing process and increases your efficiency when processing mail. Place all the mail on the scale at once, then remove one piece at a time and run it through the machine. 
The system calculates and prints the postage for each piece of mail as it goes through the machine.

Important: Each piece of mail must weigh at least as much as the Differential Weigh Trip Weight that has been set. If a piece of mail is removed that does not meet the minimum weight, the scale does not recognize the removal of the piece of mail.
  1. Select the Account (if applicable), the Class, and any other options desired for these mail pieces. If you are unsure if a particular class is valid for your mail piece, call your local post office or visit
  2. Press Enter (for "Done") when finished entering all the options and fees.
  3. Press Weigh/Rate.
  4. Select Differential Weighing.
  5. At the Start Differential Weighing screen, place the items on the scale.
  6. The total weight of the mail pieces are displayed. As prompted, remove one item from the scale.
  7. A ready to print postage screen displays, showing the weight of the item removed.
  8. Remove the top item from the stack and:
    • DM300c - If using the moistener, place flap along moistener and move towards the right. DM400c/DM475 - Load the envelope onto the feeder with the flap down and facing the rear wall.
    • DM300c - Place the envelope up against the registration wall of the system and slide it to the right until the system grasps it. The system prints the meter stamp and ejects the envelope.
    • DM400c/DM475 - Slide the side guide up to the envelope. Leave space (about the thickness of a dime) between the side guide and the envelope to ensure feeding is not restricted. Press Start. The system automatically feeds the envelope, prints the digital indicia and ejects the envelope.
  9. The same screen from Step 6 appears. Repeat steps 6 -8 for each item that needs postage.
  10. When you have removed the last item from the scale, the "Last Item" screen displays.
  11. Select Yes to rate the item or No, Do not print.
  12. The same screen from Step 5 appears. Select Exit to leave the Differential Weighing mode, OR
    Place additional items on the scale and repeat steps 6 -10 for each item that needs postage.
Note: Differential Weighing is an optional feature that must be purchased. To inquire about purchasing Differential Weighing, contact your Pitney Bowes Sales Representative.

UPDATED: May 29, 2020