I lost my phone with some unopened important document in my WhatsApp account, and I can't get the same number because I'm currently out of the country where I can replace my line. So, how do I recover my messages in such case?
Unfortunately it's not possible without using same number because Whatsapp runs only on mobile.
Whatsapp doesn't have any email id or login functionality.
Update : 8th Jan 2016.
Now Whatsapp added backup functionality using Google Drive. So you can also take your chat backup if you lost your mobile.
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