NO PURCHASE REQUIRED!
All you need to do is follow the instructions below for the latest working codes for extra free months!
You will get between 2-5 extra months for free!!
1) HP currently offers 1 month to anyone who joins their instant ink program via this referral link
http://try.hpinstantink.com/nRdnF
use code nRdnF (case sensitive) if you have already signed up (on card payment page)
2) Then Use the code: FREEINK
(when you get to the page where you choose payment card details)
for another free month.
3) Then use code HPCRAZYK2 for potential TWO free months! (this code does not always work unfortunately but worth checking!).