I had to replace the supply line that enters the house through the basement wall. To prevent water from coming in around the supply line, how do I seal the pipe between it and the basement wall? I have not tried anything yet but was thinking maybe was from a toilet ring might work.

Is this penetration point under water or just exposed to rain? What is the wall material? NO no no on the wax but a good waterproof silicone caulk would be fine.

Silicone or hydraulic cement. If the line isn't too far down, I would seal it outside with waterproofing compounds-Henry make a lot of ones to use.

Since the service line is coming through a cement block wall I would grout the opening with cement, Good luck, Tom