New sim

[Dreamyrnb]

Hi, i have always been an existing customer with o2 and decided to change my contract. I am on a 12 month sim only contract. I was asked if i wanted to change my number but i said no as i wanted to keep my existing o2 number. I've received a new sim and not sure if it should be inserted in my phone or whether i should be fine with sticking with my old sim

[Cleoriff · Accepted solution]

@Dreamyrnb 

If your old sim is 4G and you only have a 4G capable phone, then leave it as it is. However if you are thinking of getting a new phone you may as well use the new 5G sim. (you will only get 4G until you change to a 5G phone

You will need to do a sim swap if changing to the new sim Guide: Sim Swap: a mini guide 2017 update