There is no lease agreement, I live in Ohio, I moved him in to help me pay my mortgage. Recently had an altercation that has deeply affected our relationship as friends. Pays rent on time. He has never signed anything and pays rent in cash. I still care about his well being, but can no longer have my life negatively affected by his.

You have to provide some more info before we can give you a concrete answer. What state? Is there a written lease? If so are there any notice requirements in the lease? Does the roommate pay rent? Are they current with their rent?

In any case, if the person has been living there they have established residency even if there is no written lease and even if they haven't paid any rent. You will have to follow the tenancy laws in your area to have them evicted. You cannot change the locks without a court order.

Computer problems entering more information, my apologies. I live in Ohio. No written lease, I just moved him in to help me pay mortgage and he is unbearable. We recently had a friendship altering altercation about his problems. Current with rent.

... No written lease, I just moved him in to help me pay mortgage ... Current with rent.

Looks like you have a "rental agreement" as defined in Ohio's Landlord and Tenant statute (http://codes.ohio.gov/orc/5321). The term appears to be monthly. So it appears you would have to give him a 30-day written notice to get out See 5321.17 Termination of tenancy.

So, if I understand this correctly, I must give him a 30 day written notice, and if he does not leave by that time, I have to tell him 3 days before I file for eviction proceedings? I'm not charging him for this month to help him find something.

So, if I understand this correctly, I must give him a 30 day written notice, and if he does not leave by that time, I have to tell him 3 days before I file for eviction proceedings? I'm not charging him for this month to help him find something.
Pleased don't use the "comments" feature to post follow-up questions. That's for something else.

I don't see a requirement for an additional 3 days after the 30-day notice. The fact that you aren't charging him now means little. You were charging him, so it is subject to the statute I linked to.

Yes, you have to give him a 30 day written notice that his tenancy is terminated. If he hasn't moved out within that time then you have to file a lawsuit for eviction.