Why would you do this anyway?
With the mobile data connection disabled, the iPhone can still hook into wireless networks, including those at home, in shopping centres and hotels, at McDonalds and Starbucks, on public transport and at the office to surf the internet and to receive data.
It just won't be able to access data where there is either no internet wi-fi connection or where you haven't set it up. As a means of keeping mobile costs down however, the wi-fi option is certainly better than a mobile data one.
In particular, if you're travelling overseas, you'll want to disable the high-cost mobile internet option.
Why can't I just use the Airport Mode?
Airport mode is designed to allow your phone to be used on aircraft (once the plane has levelled out). It will prevent the phone from receiving calls effectively turning it into a brick that plays games.
Why wouldn't I just change my plan?
You certainly could change your plan to not include data however this would mean that it would be "permanently off" at least until you change your plan back. The way suggested in this post is better. If you get stuck somewhere and you suddenly need data access back, you can simply turn it on.
Ok, I'm convinced.- how do I do it?
On your iPhone, go to,
- Then General
- Then Network
- Locate an entry marked Mobile Data
- Slide it to Off
- That's it.