Difference between a phone sim and a data sim

[PV8058]

I’m looking to upgrade my sim after seeing tv ad saying get a 80gb sim for £20 per month. 

on looking I see this is only available on phone sims. 

what is the difference between a phone and data sim?

im looking to use in an IPad pro

[XRaySpeX · Accepted solution]

1. A phone SIM contains allowances for data, calls & texts.
2. A data SIM contains an allowances for data only., That doesn't mean you can't make calls & texts but you pay for them as out-of-allowance..

[PV8058]

Thank you for your reply. 

for clarification there is no difference except one you can make phone calls the other not.

That confuses me further as the phone sim, offers more and has a far better deal. More data and less costs.

id the data throttled on the phone sim? I just don’t understand why you get a better deal  More data for less money!

i don’t want to upgrade and find that the data allowance although greater performs slower

[XRaySpeX]

Not quite! You can make calls (& texts) from any SIM. It's just that phone SIMs include free allowances to make them; on the data SIM you pay for them.

Some, but not all, phone SIMs are sold as up to 60 Meg. All data SIMs I see are sold as "Double Speed 4G+".