Is a flat rate box the same as a regular ready post box from usps?

Question

i saw flat rate shipping and i have a ready post box i got from a local post office, they didnt have any flat rate boxes there. I saw the click-n-ship online and i'm wondering can i use the priority mail flat rate box shipping label on that regular ready post box i got from usps, it is not a flat rate box. if i can print the label on the regular box, when i drop off the box at the local post office will there be anything else i have to pay?

Answer 1

the only flat rate packaging I've seen is the large envelopes for priority and express mail and there isn't much chance to get any extra weight in there.

Answer 2

I don't know. I know the flat rate shipping boxes say that they are. They cost  upwards to $10 to mail. At least you can place any weight in them just about. I would ask. You can order those boxes of their website. They deliver in just a week or so.