Im on Three network, every now and again I get a message saying I cant connect to the internet because I don’t have Data Roaming switched on. I still get a full signal for making calls, but with the little ‘r’ symbol next to it. Should I have it switched on? Will I get charged extra for any internet I use through it?

My old Samsung Galaxy used to do that occasionally when I was in Wales, it was a fault with the phone. You shouldn’t get the ‘roaming’ notification unless you’re actually roaming.

I wonder if it’s a configuration issue, and you’re seeing it when you’re out of Three’s coverage and falling back to O2? Might be worth a call to your provider, if nothing else so that you’ve got comeback if they try to charge you.

On 3 with all u can eat data and i always have data roaming on without any implications. Only use about 1.5 gb according to my call with them today

Yes.

We don’t roam on each other’s networks in the UK because they are all nominally nation-wide. So you can leave it on*, and nothing will happen because the networks don’t have roaming agreements.

In big countries like the US that have regional carriers, you can roam whilst you are still in the same country. However the real reason it’s there is to stop you spending shitloads when you go on holiday without realising it.

* I’m not a phone expert though. You can also leave it off, won’t make any difference!

Data roaming only applies when you go abroad for us. I turn it off so I don’t get caught out when disabling flight mode getting off a plane in a foreign land with all my emails suddenly flooding through.

Can get errors on welsh coast especially on Anglesey as sometimes picks up carrier from Eire and gets confused. Happens every time I’m in Holyhead.

You may get the same problem in Cumbria and Northumberland in a few years….

I believe that data roaming charges across Europe are going to drop significantly:
http://www.bbc.co.uk/news/business-28096678
Not going to disappear yet, though.
Sadly.