How do different mobile carriers not set up new customers with the same phone number?

Question

How does a new T-Mobile customer and Verizon customer not get the same number? Do companies share the same number generator? How can Apple systems tell a number doesn’t come from apple messager?

In: 6

Answer 1

I got my first mobile phone in 2001 when my daughter was born. Since then I have switched service many times with Cingular, AT&T, Boost, Straight Talk and one other small company whose name I can’t recall. Every time I was able to port my number from carrier to carrier.