Voucher code to save £20 off the upfront cost of any phones on O2 refresh at O2 shop online. Popped up for me when recently ordering a new phone as an upgrade (they offered me a 3 month early upgrade and paid of £89 left of my device plan, couldn't say no!)
Worked when ordering my new OnePlus Nord, just enter the code at checkout. If there is no upfront cost for the phone (there wasn't for mine), just add £20 (edit the plan) which will reduce your overall airtime by £20, so you can take advantage of the offer
Tested code by adding a Galaxy S20 5G & iPhone 12 pro max 5G to basket and worked for both so assume this is working on any phone.
Phones in stock will be delivered free of charge the next working day (unless like me you order an out of stock phone and had to wait 2 weeks )