Metered mail users must mail items on the same date printed on the postage label's postmark. Users can print a corrected label if they miss the original mailing date. The first corrected label is free, but additional corrections incur a fee.
Employees should deliver commercial business mail to the business mail entry unit of the post office. The USPS recommends calling the local post office to determine the most convenient time to drop off mail. The hours of the business mail entry unit may differ from the official post office hours. Employees cannot deposit business mail into a collections box or give it to a letter carrier.