How long is apostille valid?
If you’re wondering how long is apostille valid for it’s basically valid forever. USA apostilles and authentication certificates do not have expirations on them.
With that said most foreign countries can, however, create requirements where they will only accept apostille or authentication certificates that have been issued within a certain amount of months or years of when you submit your documents to them. Most foreign countries for example will only accept apostilled FBI background checks that are 3-6 months old.