Have 2 O2 SIM cards, can't tell which one is the active one, rn in a O2-unsupported country

[GZ]

So basically, I am currently living abroad from the UK. I have 2 O2 SIM cards but I can't tell which one was the SIM card I was regularly using in the UK & which one is the expired one. Normally, this would be simple to find out if I was in the UK & could just test the internet connection/SMS capabilities of each SIM cards, but the country I'm in doesn't support roaming from O2, so I'm not sure what to do

[Bambino]

@GZ If the country you're in doesn't support roaming from O2, you can't use either sim so why do you need to know?

[GZ]

I'll be heading back to the UK soon and I have to catch a call or call someone with my UK number when I arrive, so it'd be more ideal if I figured out the correct SIM card beforehand.

[Bambino]

@GZ When you return, the process of elimination should be fairly quick. One sim will work, the other won't.

[GZ]

Well yes, though I was just generally wondering if there was any way to figure it out outside of the UK lol

[Bambino]

@GZ There would be a way to figure it out if you were in a country that supported O2 roaming, but as you're not you'll just have to wait until you return. Most times I find that I can get a signal while my plane is taxiing after landing, so the wait isn't long.

[jonsie · Accepted solution]

It won't help you at the moment unless you use Skype to call O2

They can get the mobile number from the sim serial number

Numbers to call can be found here

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