We have an awful smell coming from our master bathroom. I thought it was a sewage smell .(My husband thinks it smells like rotten meat.)At first I thought it was the toilet and I had a plumber out who changed the ring. It did not fix our problem, so I had another plumber come who checked under the house and did not find anything. He thought maybe the smell could possibly be coming from a dead animal under our house or in the walls.
I checked all of our drains and none of our drains stink, but I did notice a stinky space under my bathroom cabinet. How do you tell the difference between sewage odor and dead animal smell. Should it smell like rotten eggs because this doesn't? I figure my next call should be to do a smoke test to check for a leak, but I would think I could smell sewage in the drains if there was a leak. Maybe I need a pest guy. I just want to call the right person so I don't have to pay again for nothing and still have the problem. I am not an expert on smells, I just know this one is a bad one.

Sewer gas smells exactly like the soilds that get flushed down the toilet so there is not mistaking that. Dead meat, smells like dead mice to me. One tiny dead mouse will stink to high Heaven but only for about 2 weeks, then its over. How long have you had this issue. Is the floor of your vanity bone dry?

Yes, everything beneath my sink is dry. The smell does seem to be lurking there, but not as strongly as within the crack next to my cabinet. It has been about 2 weeks since I first noticed it. My husband's vanity is next to mine with a separate cabinet and there is no smell there.

Very well could be a dead rodent. If the smell is pretty much gone by next weekend I'd ignore the issue.