Poor connection in good coverage area

[Fi-Richardson]

I am in RH2 Surrey where the 4G coverage is supposed to be good inside and outside. I recently switched back to O2 and have found that  the max bars I get are generally 2!  everything runs really slowly. 

I have switched my phone off and on again

 and reset my network settings in 2 local locations and it hasn’t made any difference. 
is it my Sim or my phone? 
is this the best I can expect or is there anything else I can do?

I was getting better coverage with Three and I thought that was poor. 

[MI5]

@Fi-Richardson 

Number of bars is irrelevant to signal quality.

What data speeds do you get?

https://www.speedtest.net/

[Oxonian]

@Fi-Richardson 

A few things that might help :-

Guide: How can I sort out my network issues? 

Guide: Is the network down for me or everyone? 

My Network App - Find Out More About Your Network Coverage | Apps | O2

https://www.o2.co.uk/apps/my-network

[japitts]

There's 2 concepts you need to separate here.

1: Quality of coverage - is what your on-screen bars indicate and is a basic indicator of whether your phone has network service

2: Depth of coverage - is what capacity/spectrum is available on your serving site and which dictates the data speeds you will achieve.

O2 has some well-documented issues with data speeds on a national basis, although there will always be local variations.

[Fi-Richardson]

4.24mbps

[MI5]

@Fi-Richardson 

That's about average for O2 and likely as good as you'll get at your location.