[ehPReth]

Any toll-free number you call - at least within the +1 country code - can see your outbound number even if you hide it.

So if you’re in the USA and you have ever called your bank’s toll-free from your mobile they already have your cell phone number. you can try to sell yourself by googling for toll-free ANACs which will read your number back to you

[b112]

This is helpful info, but I use voice on my mobile sparingly, and use my voip line most of the time. (I have a cordless + desktop voip phone at home and work).