How to fiX a water leak through a chimney?

It sounds like the flashing around the chimney needs to be repaired. I would hire a professional as many times the leak will travel to the lowest point before you see the water.

Get a few bids from different people to see if they all agree as to where the leak is...

I would call the contractor back. The chinmey was not properly flashed.

You need to call the roofer back to check the flashing. Also may need mason to tuck point the chimney.

Hi Susan! This is one of those projects that can cost a lot of time and money if not done properly. I would have a licensed roofer come in, who would guarantee their work. If you have a warrantee from the roofing installation, that might be a good avenue to explore.

I had the same problem with my 80 yo house. I had the roofer come out each year to recaulk around the fireplace as I was told the roof wasn't properly installed around it. $50

I also had a new chimney cap of metal made to prevent water coming down it as it was a very wide chimney.

here is the recommended style for the PNW torrential rains.... https://www.youtube.com/watch?v=1Abr7hbTXqk

You should have a roofer come by as well as a mason to check on the chimney (I'm assuming it's brick). Leaks are so hard to find, they could be coming from the other side of the house.

You have described our problem exactly. For years many roof repairs, roof replacement, new cap all would seem fixed. Then would come the LONG soaking Florida rain and again the dreaded drip drip drip always after we had repaired the drywall. We finally used Seal Crete on the chimney bricks, sprayed heavy many coats and the problem was solved for quite some time. The Seal Crete goes on milky but dries clear so don't panic. You do need to reseal every couple years.

Worked for us...