The difference lies in postal savings. It comes down to how your piece is designed, your data is prepared, and your mail is processed. If your piece is below 3.3362 ounces, you will only be charged by the piece. If your piece is over 3.3362 ounces, but under 16 ounces, you'll be charged by the piece and by the pound. Click here to see our Postal Classes and Rates.
All Standard mail goes by truck.
Nothing goes by air. Delivery times are faster if your piece has been prepared for Automation Mail. This helps to give us ample supply in case of printer shortages or machine damage. It is critical today for window envelopes to have larger window sizes for Automated Carrier Route mailings that require an endorsement line and postnet barcode. In addition, with the availability of an additional Planet code for Confirm and Origin mailings, an additional barcode above the endorsement line requires the window to be much larger.