When using printed postage must the package be mailed the same day? Or is there another time limit? Next day, etc?

The package should be mailed the same day.  However, I know that if I miss the mailman, or drop it in a blue box after the pickup time, then the previous day's date is accepted with no issue.  However, if I take it in to the PO, they will often run a 0.00 strip with the current date on it.

You can change the date when printing postage, though, so if you know you won't mail it the day you print it you can tell it the day you will mail.  With printable postage I mail the same day, unless I'm packing them up at night, and then I'll put the next day's date on there.

Printable Postage mailings should be mailed on the day you selected. I believe it is ok to mail them earlier but not later.

I always pick the latest day to mark mailed as it gives me more flexibility. I normally mail sooner so change the mailing date on printable postage but have forgotten a few times and never run into an issue. I'm sure that it would still be accepted a day or so late as well.

From what I've been told by postal employees (who we know are not consistent from day to day) is that one day late is OK.  After that, IF they catch it, they'll send it back to you.

I was also told that if you put it in a blue pickup box after pickup, then it's considered mailed on the date you put it in. So if you have a label dated 3/18 and you put it in the blue box on 3/19 after normal pickup, if it's picked up on 3/20, it's counted as a one day late label.

Thanks, all. I've just started using PBS postage because the 5 cents extra (over the PBS & PO combined cost of DC) is well worth it in avoiding the local PO's hassles with PBS DC. I hadn't known that I could change the date on the printable postage. Thanks again for the information.

I have even received a book before the date printed on the label!  (someone obviously put the furthest out mailing date then mailed it days before that!)

I have also received books that got to me before the date on the label.  At first I couldn't understand why until I started using printed postage.  I've never had any issues mailing it a day or two before the label says.