How to make an international collect call from London to USA?

Question

I will be in London for a few months. I've contracted a health insurance plan. Its WEB page says "If you ever need any assistance, just call 1-410-XXX-XXXX in USA, collect call".

This number seems to be a pretty normal USA number. How can I be sure that a call will be collect (free for me)? If I use a British cell phone or land line, what numbers (prefixes, I mean) I must dial in order to be sure that the call will be free? Or the only solution would be to ask the British telephone company's operator for assistance?

Answer 1

Best Answer - Chosen by Voters

Those calls are only free if you are calling in the country they are in. You will be charged if you call outside the USA or from a mobile.

Answer 2

You can go through an operator, dial 100 or 155 for the international operator. Alternatively you could dial the number yourself, just start with 00 (the international exchange) and then 1 (the USA country code) and the number the company gave you.

Answer 3

Use the international operator on 155