What is a 5G SIM? Generally, 5G SIMs are physical SIM cards that offer up to 20x faster speeds than standard, 4G SIMs . To get started, simply insert the card into the back of your 5G-ready smartphone – just as you would with a standard pay-as-you-go SIM.
Read moreIs 5G SIM different to 4G SIM?
SIM cards from the 3G UMTS network onwards are backwards and forward compatible, and mobile phones are backwards compatible. So, a 5G SIM card will work in a 4G phone, but will only allow you to access 4G, 3G and 2G networks if used in a 4G phone .
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