Is Tap Water in San José safe Drinking water?

Assuming you're not in the ghetto area of San Jose, yes, very safe.  That's been my experience and what I've read.

I've stayed in many cheap hotels and went to many hole in the wall little sodas in San Jose and all over the country here and never gotten sick from drinking the tap water.
The only time I ever got sick from water was when I swallowed a mouthful while swimming in the ocean at Jaco years ago. Not sure if it's still that dirty but at that time it was known to be dirty - (but I didn't know).

I have lived in Costa Rica for almost 40 and the water is safe to drink almost everywhere in the country including San José. —unlike Ecuador, Nicaragua and Mexico.

Christopher Howard
liveincostarica.com