I'm not sure what happens if you order a SIM card, activate it but don't buy any membership at all.
I'm not sure that the card will be any use in such circumstances - e.g. you may not even be able to receive calls or texts unless you buy a membership at least once?
The normal rules for suspension of a SIM card are explained here:
https://48.ie/legal/terms-and-conditions#7
Maybe the same applies if you never buy membership at all - i.e. after 6 months your SIM card is suspended and after another 2 + 5 months it will be removed altogether from the system and the associated number "recycled".
However to be sure you should ask 48 support.
Why do you want to get a SIM but not buy membership?
Hope this helps.
