Hi!
I am wondering if it is okay to use USPS airmail stickers even though they are obsolete functionally. I asked my local post office if they had any and they gave me some. I wanted to use them more for decoration purposes on postcards and letters. Is that okay? Any additional information is deeply appreciated as well!
Thank you! 
I occasionally use the old Air Mail stickers on my postcards - I like the old fashioned feeling of them. Back when I worked in an office, I even printed out some of my own to use. As far as I know, there is no prohibition on using them - it just makes the writing space smaller.
Thank you! I saw other snail mail friends talking about them in the Instagram community and was curious!
Here is a reply from user @maleko on this topic when I asked about airmail stickers:
“When I go to my neighborhood post office to buy international rate stamps, the postal workers there often ask me if I want some airmail stickers. They’re free, but I think I read somewhere that they’re “new old stock” that USPS isn’t printing anymore, so they may not be available at all post offices.”
Here is another explanation from @AMDGIHS2019 (whose username I just figured out, by the way; took me way too long for someone who spent 6 years in Jesuit schools 
):
The blue Air Mail stickers (that I showed in an earlier post in this thread) are not required but are recommended. They are free for the asking and serve as an “eye-catcher”, to “jolt” (her word) the USA Letter Carriers and Sorting Personnel into noticing that a piece of mail is international. Anything that can help the humans route things correctly before the hand-off to the machines in the postal processing plants is a good thing. These USA stickers have no meaning for other countries’ postal services (just as other countries’ air mail stickers have no meaning to other destination countries, including the USA).
I hope that helps! 
It does! Thank you so much! I can’t wait to use them now! 
I would love to see them on cards sent to me. 
Our postmaster ordered some for me last year but they were pretty large making the address space cramped. They also told me they really don’t mean anything anymore. I like them but find it really cramps the address space.
I found a slip of them when I was doing some cleaning. I have one left to use.
I actually asked three post offices here in New York, all of them told me they hadn’t any left 
They all told me it’s unnecessary but not disallowed.
I would definitely be using them if I had them!
I just recently joined Post Crossing and found that if you go to the post office you can request them to stamp it Airmail. I thought it added to the card.