I’ve tried to find the answer to this question online but can’t find anything that explains what I’m wondering about. Okay, so I received a US domestic postcard with a LOT of stamps, but they were all small denominations and added up to only 20 cents. A US postcard is 44 cents now. So here’s my question: how does the postal service know if you’ve got enough postage when you use a bunch of stamps? Does a human actually count up the stamp values? That seems like it would be very time consuming. Does a mechanical scanner read the stamps? What about the very old ones? The postcard I received did not arrive ‘postage due’ and it did not appear that any stamps had fallen off in transit. I’m not planning to cheat the system, but I’m just very curious about how the sender of my recently received card got away with it. Anyone work for the postal service who can answer this question. I’m puzzled. Thanks!
The end of this reply has a good explanation:
Maybe this answers your question?
I assumed it was pretty much on the honors system, with only the occasional nosy clerk interfering to cause a problem.
Everything is automated…
Wow! I’ve always been amazed by the postal system. These videos prove that the system is amazing!
Last summer I had a mental lapse when adding postage to a significant batch of postcards I was sending out (I blame the summer heat!). For some odd reason, I was using the old postage rate so I was missing about 4-10 cents on each card! I didn’t notice until about a week after I posted them - and actually, that is how I got started on the Forum! I had so many questions …
I came to accept my mistake and that most, if not all, won’t arrive. Years ago this happened as well, and none arrived. But! My summer 2022 batch mostly did arrive to their destinations! So as @Johnk60 stated, it’s probably a honors system depending on the clerk. Personally, I thought the sorting machines took care of calculating the postage adhered to mail!
I am a postal office worker. The only person who tends to use a lot of stamps on letters at my job is me, LOL. We typically assume that when someone drops mail into the slot, they all have Forever stamps. We also send our letters off to a larger post office, which I want to believe they preform double-checks before sending the letters out. Unfortunately, I am not sure. I have caught a letter without a mailing address, though! It only had a return address and a stamp.
Most of our letters are postmarked through a machine at the larger post office, but I personally hand-cancel the ones I send for Postcrossing. It makes them more interesting, in my opinion.
Op. Mostly machines cancel them. Other times not and they still go thru. Without a cancel. There are people who simply don’t know what the rate is. Others use stamps that dont necessarily have a value on it and assume its what it is.
The post office hires ALL the time and the turnover of new people ofren inexperienced shows all the time. Inasked for a handcancel once. The guy asked a co worker if it was allowed. His co worker was like yeah and the guy only cancelled one stamp out of 4 that were on the envelope.
The short answer is they don’t know. If you just drop a postcard in the outgoing mail where it won’t be seen by a human until it’s delivered, they won’t notice. For instance a blue mailbox at a post office- people drop hundreds of envelopes and postcards in there and then they all collect in a cart that gets dumped into a machine that sorts everything, and then gets sorted into delivery order by more machines, so we pretty much just operate on the honor system here unless you are handing the cards off to a postal clerk to get hand canceled. But even then, postage rates increase so often that it’s hard to remember how much postage you need to apply!