charged extra month for changing tariff on sim only plan

[Nath92]

I recently changed tariff for more data part way through my billing month. When I received my bill it was higher than I expected. Upon looking at the breakdown it was somewhat confusing... There was a charge from the date a changed tariff to end of my billing month, a credit amount (I'm presuming is for not being on my new tariff for whole of billing month) and lastly a charge at the price of my new tariff but dated for my next billing month period which I should not receive for another 29 days. Upon speaking to a representative I was informed this is a line rental charge whereby I'm charged an extra month for having changed tariff.

Has anyone else experienced this or aware that you get charged an extra month for changing tariff? Nowhere when changing or in my emails did I read about this, most likely tucked away in the small print. Also kind of confusing the way it was written in my bill instead of simply saying charge for changing tariff. I was on a 24 month sim only deal with 20GB data but increased to unlimited data.

Thanks

[Enlli]

You are not charged just to change tariffs. Customer Services making it up again.

[madasaf1sh · Accepted solution]

@Nath92 

It will be prorated, as you pay in advance for your airtime, so you will have been charged on your old tariff, till you changed to your new tariff, then the time till your next billing date then a full month from then on, so your bill is correct. 

This is how all networks work, and the best advice is to wait till your billing date and then change the tariff, never do it mid month.

[MI5]

@Nath92 

You do not pay a month in advance on a tariff change. That's complete rubbish.

The only extra you should pay is the pro rata amount for the new tariff.

Next month you will pay the full amount for the new tariff.

Makes no difference when you change as it's always pro rata.