I love horror but apparently I don't vibe with a lot of recommendations I find online.
I'd seen so much hype about Event Horizon and I absolutely hated it and didn't find it scary. I just watched Late Night With the Devil and whole it was definitely enjoyable, it wasn't the least but frightening. I also just watched Let the Right One In and really didn't like it. It also was not a horror movie in my opinion.
I will say one of my favorites is Sinister or the first Conjuring. Sinister for the stomach twisting dread and suspence throughout and Conjuring for the same.
There is a particular type of emotion which "The VVitch" and "Hereditary" get absolutely perfect. It's actually not really my favorite type of movie; it's not particular scary, per se, but it is just some stuff that is really awful that you don't want to see. If you don't want that, they may not be good, but if you vibe with that particular emotion they are hard to beat for it.
The HBO "Chernobyl" miniseries is absolutely straight-up horror. It has pretty much all the elements of a perfect horror movie, except it's (with tiny exceptions and artistic licenses) all 100% true.
"As Above, So Below" is fairly good "normal" horror of a fairly unspicy flavor.
That's honestly all I can think of that really does it well. Horror books in my experience are far better. "The Shining," "Pet Semetary," "Night Shift," and "Skeleton Crew." Also lots and lots of HP Lovecraft; the "Dunwich Horror" collection is wonderful.
There has got to be a term for the particular type of ... restlessness(?) that movies like VVitch and Hereditary inflict. It's not exactly horror, but a distinct discomfort that I can't quite name. Talk To Me also got close for me but not as far as Hereditary.
Oooh yes. I'm with you and the other commenter that that particular feeling of dread is really really great. Hereditary, Midsommar, and VVitch definitely all fit that bill. I've heard the same for Lights Out, so I'm going to give that a go too.
Also Chernobyl is so so good. I've seen it a few times now and oof.
All films from Robert Eggers with his debut "The VVitch" and Ari Aster with its debut "Hereditary" are highly recommended although not all films are 100 % horror movies.