Can send/receive text when out of data

[#1]

When my son has used all his data he can’t send or receive text messages. Including iMessage. Why is this? He can only do it when he’s at home on WiFi.

I’m on another network and my unlimited texts and calls aren’t linked to my data.

Any idea anyone? TIA

[#2]

iMessages are sent using data and therefore need either a Wifi connection or cellular data availability.

[#3 · Accepted solution]

You can turn text messages on for when iMessages isn't available under Settings > Messages > Send as SMS - that may help with the sending part.
Not sure on receiving.

[#4]

Thank you I didn’t realise that

[#5]

Thank you, that’s resolved it

[#6]

Glad to hear it