The UN appears to be closed to the public for now due to the pandemic so mail in is the only option. My latest experience, I mailed some cards in on 8 March for a direct swap and I was told the cards were postmarked the 19th. Assuming it takes two days to travel within New York City that would be about a week’s delay. Since you save the mailing time, going in person should be faster but that is not allowed right now. Before the pandemic, the ones I brought in person were not postmarked until three or four days later. But still, that is unacceptable when the standard is dispatch on day of collection, as you would get at a regular USPS office or postbox. I do not see any reason for the delay, unless all the UN mail including the official stuff just sits around until somebody feels like taking it to a USPS office.
Anyway, the rates don’t change until 29 August if that helps.
I believe I saw it on Wikipedia, the UN Postal Administration admitted it has no interest in providing postal services, hence the closing of the USPS branch onsite. The sole purpose is to vacuum up the collector revenue. Sounds about right if you ask me. Stamps with no postal “ability” are taboo to “serious” collectors so I suppose the UNPA goes on that to keep their stamps “legit” (just good enough to get a letter somewhere someday). They should just change the name to the UN Label Printing Administration.
Every now & then I will put UN New York stamps on my cards and send them to the UN post office for processing. I do just a few and infrequently so as not to overwhelm them (their PO is really for official mail not for the public but they do allow it). Its adds a bit more travel time but some may appreciate the different stamps. One recipient told me he used to work at the Geneva HQ post office so he was very happy to get NY stamps on his card
I found this thread only today.
I hope, I’m able to engage a bit in the discussion. 
I visited the UN postal service in Austria on Saturday. The post office in the UNO building is still closed, but there are some “special exhibition days” where you can by UNO stamps and drop your mail. As I don’t know how to call these in German, no idea how to explain it in English
I pointed at a Dollar-stamp and told the lady, how sad it is, that I can’t use it in Austria. Answer: I can mail it via NYC to you!
So I bought a stamp from NYC and from Geneva to mail a card for myself, to see how long it is going to take.
I’m so excited, because this really opend a wide door for collection for me.
If it works, maybe somebody is interested in swapping?
I’m very interested in The Hague ones.
Nevertheless, first of all, I have to figure out, if the postcards for myself reach their destination.
Earlier this year I posted a card from Vienna to Vienna and I think it travelled around six weeks?
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It looks like it was sent from New York. Maybe the sender was traveling and did not change their country code.
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You may buy UN stamps online and send them your mail with the UN stamps (in an envelope) to the headquarter. They will then cancel the mail and forward it: Things You Should Know - UN Stamps
@pumuckl often does this, maybe he can explain more detailed 
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Yes for sure. They’re interesting philatelic items 
Hi All 
yes they are highly collectable, sso if you dont want to keep such envies I will give them shelter
The workflow is mainly like this:
Someone wants to send their cards over UN Postoffice in New York, so they get according stamps
( postage is the same as for USA ) and puts the postage on each letter or postcard.
Then they send it to UN Postoffice in New York in a bigger letter all together.
UN Postoffice in New York will receive and open the big letter and process the single letter and postcards.
I do this for UN Geneva and I have a written letter template which tells them how many letters and postcards I have and that they should postmark and post them .
@InkGoesWildAlaska how long did it take to reach you ?
for any additional questions feel free to PM me
Looking at the denominations of the stamps, these appear to be older issues. Perhaps the mailer prepared them some time ago and then mailed them as needed. I have a number of First Day Covers bearing such stamps.
@Cassiopheia and @pumuckl have already explained most of it. You can send your mail to the UN offices in New York, Geneva and Vienna for forwarding. However, you have to use the stamps issued by the respective office (New York in US dollars, Geneva in Swiss Francs, Vienna in Euros). Old stamps remain valid as long as the currency still matches. There are old Austrian UN stamps in the former Austrian Schilling currency; these are no longer valid as Austria now has the Euro currency.
Recently I sent an envelope to myself in a mailing, with Hundertwasser stamps from 1983. You can still find many old UN stamps on Ebay.
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someone mention about it being sent to the united nations post office in nyc. the 56 days would of been to get there from poland and then sent out as it usually takes up to a week for mail to arrive for a domestic latter/postcard (or use to be - who knows now).
i saw the postmark and the person sending it was at the unpo, he would have to personally request this postmark. but as it was sent to the unpo, they had requested this postmark. as you could see, after leaving the unpo, went thru the normal usps sorting machine as it has the new york city cancelmark.
before the pandemic, would make a trip to nyc and visit the unpo to send out my holiday cards. would buy stamps from dealers earlier from dealers at stamp shows (usually at face or a little discount depending how much you buy. i had send some postcards in 2017 and most arrived. some, the stamps were removed and delivered or the postcard didn’t arrived at all. these cards were sent to russia and china. guess the post office employees like un postage stamps. oh, forgot to mention that they were the 70¢ halogram stamp - everyone who got their card mention about that stamp.
I use the UN mail occasionally…place UN stamps on cards, put them in an envelope and send to the UN Post Office. They mark and send them along
They must have sent it to the UN under cover with UN stamps on the cards they want posted from UN NY.
I see from your photos that they are now using the proper UN postmarks AND applying them to philatelic standard. I gave up on the UN post even though I live not too far from it because of the haphazard postmarking and slow dispatch. See my previous posts on this same thread. If they truly are sticking to philatelic standards I might give them another chance despite the slow dispatch.
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A postal stationery envelope arrived from the UNPA office in New York. It was sent from Germany to New York in mid-November and returned after almost exactly one month.
I find it interesting that the letter was cancelled twice. Once on 29 November and once on 02 December. Is there a system to this (e.g. incoming and outgoing postmarks?) or an oversight?
Hi @Speicher3
yes looks like the first one is the philatelistic one 29th and then they use the second one (2nd of Dec. ) for the real “exit” date This happened to my letters aswell
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