A buddy of mine has a mostly-defunct vending route. (Fifteen years ago he had 200 COCOTs; that business is entirely defunct now).
The locations where he has his remaining vending machines have a cell phone number that's been his for a decade or more; it is AT&T, and he pays a monthly bill to keep his service and 250 "free" minutes with no roaming charges. (He is also an OTR trucker, so "no roaming charge" is important).
Is there any way he can convert this from a monthly bill to a pre- paid plan AND KEEP THE SAME PHONE NUMBER?
I'm not sure what the COCOTs have to do with a cellphone number, but here's what I know. At least for T-Mobile (which I have both prepaid and monthly billed service) you can convert from monthly billed to prepaid or vice versa. All you have to do is call regular customer care and request that your account be converted from monthly billed to prepaid. They'll even give you $5 credit when you switch from monthly billed to prepaid. I'm told that the process to convert takes ~24 hours. Even if you're not with T-Mobile you can port your number over to another service whether it's T-Mobile's "To Go" service, AT&T's "GoPhone", Sprint or Virgin. Keeping in mind that you need to arrange the port with the mobile operator you're going to and not from your present mobile operator. These days ports from mobile operator to mobile operator take hours rather than days since we've had number portability now since November of 2003.
Do keep in mind when switching from monthly billed to prepaid that prepaid more often than not does not roam on to other systems with the exception that T-Mobile has a limited amount of roaming and TracFone generally will roam on anything that uses the same technology as the handset you have depending on whether you got a GSM TracFone (which will work on both AT&T, T-Mobile and other non-national GSM networks) while the CDMA TracFones will generally work with all CDMA networks such as Verizon, Sprint, Alltel, etc. Most prepaids will let you make domestic calls for just airtime, but you need to check to be sure.
I think though that if I was an LD trucker I'd want the surety that I'd be able to call anywhere and for that I'd opt for at least the minimum monthly billed plan.
T-Mobile did it for my Aunt a couple years ago. She treats the phone as an emergency phone for the glove box. We got her a phone for $50, put $100 on the prepaid card, then every year (actually we do it every 50 weeks), we add $10 to the prepaid card. So, she kept her phone # it costs her $1 per month - that includes all taxes.
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