@MayaLocke There are what are called “roaming agreements” between carriers. That means that if you have a plan that offers a “Nation-wide calling,” and if you get into an area where your company doesn’t have their own towers, they’ll “borrow” another carrier’s towers. Per the agreement, the Other Guys sell their air minutes at a cut rate, which is much less than the $.49 per minutes (or whatever) you’d be charged if you hadn’t bought into the roaming agreement (Which you did when you signed up for the “Nation wide calling” plan.) I’ve been out of it a long, long time, but I’m pretty sure that the four major carriers, the Big Guys, are now ATT, Verizon (Biggest), Altell and US Cellular (Less Big). All of the other guys, like Cricket and whomever, do not own their own towers. They’ve all signed roaming agreements with the Big Guys and use their towers. And pay a portion of their income to them.
By the same token, if you have service with one of the Big Guys, like US Cellular, and you go into an area, you’re going to be roaming off of Verizon, whether you know it or not. So basically, all the carriers have pretty much the same coverage because they borrow from others when the coverage isn’t there.
If you ever want to know whose towers your using, dial 611, or *611. The message will tell you who you’ve “contacted,” therefore whose service you’re using.
I’m pretty sure this info is correct, but I’ve been out of the industry for years and years. If anyone out there has different information that they’re SURE of, please weigh in!