You have to tell them you are leaving as you you cant afford it anymore as it is to expensive.
They will try and cut some of your broadband speed etc to make it cheaper. Just tell them you are happy with what you have got but would like it cheaper.
They will waffle on and say they cant cut it down anymore. You have to tell them you are not happy with the price you pay and you would like to give a months notice. Do not backtrack on that and they will give you a date when you will leave..
Hang up the phone and wait. They will get back to you in a few days and if you are still not happy on what they offer just say sorry but I still want to leave.
Sit back and wait for the next phone call and see if the offer improves.
If you have been a customer for a long while they will usually give you a better deal. But every year when they put their prices up you have to go through all that again..
They will tell you that they have checked and you cant get it cheaper anywhere else. just tell them you are happy with what you get but cannot afford the price anymore.
rather than loose you they will normally give you it cheaper.
If it gets to the point where they dont phone back and maybe you have only a day left before you get cut off you can phone them and tell them that you have decided to stay with the, But it should not come to that..
I would say that they are very expensive but you pay for what you get and in my opinion they are one of the best ISP,s about.
Be polite but firm. I had to do that every year till I moved to an area that does not have Virginmedia. Usually the best time to do it was when they put the prices up and they do that every year, So basically you can cancel your contract with them without it costing you any future payments
Good luck, there is nothing wrong in trying to get a decent price that you can afford to pay from them.