I have a phone under contract with orange, the phone contract is in a company name that has now ceased to trade over four years ago although I have continued to pay for it monthly, if I wish to default the contract who would the phone company chase?
By using the service you have entered into a contract with Orange.
Initially they will chase the defunct company. Then they'll scratch their heads for a bit and chase you - assuming they can trace you. The service will have been cut off well before they get to this stage.
when did you last renew the contract ie by upgrading your phone or something?
If you took it our 4 years and the original contract has expired then its just a rolling contract and you should be able to get out of it with a notice period.