Whatsapp, Keeping the number on the new phone but without the old sim card Whatsapp, Keeping the number on the new phone but without the old sim card.
Ok the situation is I love my old number and to be honest don't want to ask everybody to change my number again and again.
But I do not have the old sim card, and that bums me out. If there is any way to achieve this?
Whatsapp checks if there's a sim card installed at the time of boot. 
So as long as you have a sim card installed, it shouldn't be a problem to your whatsapp account (The old one)

I've switched sim cards and it hasn't affected my whatsapp account.
The problem of verification arises when you boot your phone without a sim card.