My boyfriend and I recently broke up and he is not on the lease. He does not pay any of the bills and only one bill is in his name (internet). I pay it too. I want him to leave but he says I have to formally evict him. We live in Phoenifx AZ. Is this true? Do I actually have to go through the courts for this?

Yes, he is a resident there if he receives his mail there and has been living there for awhile.

Yes it is true. He has established residency and you can't just kick him out. However, it may not require court. Did he ever pay towards the rent, if so can you prove it?

The process for getting a resident out of your home goes like this:

Step 1: Serve notice that you are terminating tenancy. If you can prove there was an agreement for him to pay a share of the rent and he has not done so, you can serve him a 5 day pay or quit notice. But if he pays in full within the 5 days, he can stay. Otherwise you need to serve notice to include one full rental period. So if your rent is due on the 1st of the month, then you have to give him until the end of June to vacate. The notice must be in writing.
Step 2. If he ignores the deadlines in the notice of termination then you will have to go to court. You start with filing for an eviction order. A hearing will be scheduled and you give him notice of the hearing. That may be enough to show him how serious you are. Otherwise the hearing will be held, you will get an eviction order and, if he still defies it, you can hire a sheriff to physically remove him.

You could try something expensive and risky but quick. Pretend that the landlord has agreed to end your lease May 31 out of sympathy. Move everything into storage ASAP and stay with a friend. With no furniture and housewares (assuming you own everything) and looming immediate eviction by the landlord for what you could say will be trespassing (not true, and he may know that), he might just leave, and you could move back in. It's a bluff and a long shot. If he decides to wait it out, you lose, including being evicted yourself. You might get a sense of what he knows and what he might do just from starting the process.

Not suggesting you do this for a minute. It's a terrible idea, but not illegal. Lawyers engage in deception all the time, starting with putting criminals in suits and ties with haircuts.