Late to the party just wanted to throw my dime in for October.
If recent isn't a must. Because honestly I find alot of the older Horror movies better. They build more suspense and better stories. Instead of immediately shooting their wad via CGI.
Examples:
Ghost Story (1981) [ Fred Astaire, Melvyn Douglas, Douglas Fairbanks Jr., John Houseman, Craig Wasson, and Alice Krige.]
(maybe the best gost story I have ever seen)
The Fog” (1980) [Adrienne Barbeau, Jamie Lee Curtis, Tom Atkins, Janet Leigh and Hal Holbrook.]
(I mean Jamie Lee and Barbeau in same movie scream queen perfection..stay away from the remake it's trash)
The Shining” (1980) (kind of obvious one you have probably already seen, but in case you haven't.)
Poltergeist (all of em) (Not deep but satisfying, guessing most have seen them but for the younglings that haven't, nice mix of campy, horror, and comedy).
The Exorcist (1973)(You have probably seen it, but it's the classic. There is a reason this is normally everyone's number one scariest movie of all time)
The Omen (1976)(another you likely have seen but if not, similar to exorcist in some ways but instead of abeject horror it's abject dread)
The Wicker Man (1973) (like the six sense don't let anyone tell you about it or how it ends)
An American Werewolf in London (1981) (Best werewolf movie ever made, one of the greatest practical effect movies)
Brotherhood of the Wolf (2001) Second best werewolf movie ever made...and HOTTIE Monica Bellucci in her prime. More action.
The Witch (2015) (one of the very few modern horror movies that builds the same suspense as classics, well done)
Vampires 1998 (more action then scary, but possibly my favorite vampire movie in that they actually do what you would WANT to do when facing vampires instead of being idiots, and James Woods, and Sheryl Lee make it a campy classic. I just like how it flies in the face of all the usual vampire tropes)
The Thing (1982) (another you probably have seen but just and absolute must see classic, also can be beconsidered Alien series Beta test movie, the other greatest practical effect movie)
Rosemary's Baby (1968) very disturbing, arguably more disturbing now the more we know about Polanski....fiction or documentary? If ya know you know. There are cults that believe this crap.
Don't Look Now (1973) (donald Sutherland, this one deserves to be in the group of classics you have already seen and yet is often overlooked. Well done british horror, and good acting)
Jacobs Ladder (1990) PTSD as horror....Kinda surprised this isn't being talked about again....given our number of vets etc.
The Devils backbone 2001 (Excellent Spanish horror film and ghost story)
Ringu (1998) (you probably have seen it or certainly the memes but one of the best Japanese ghost stories, and they excel at ghost stories)
The Wailing (2016) (Korean ghosts story more dark comedy then horror, but very good)
The Sixth Sense (1999) I assume everyone have seen this one, I don't know anyone who hasn't at this point, but none the less for the 1% who haven't seen it, see it before it's ruined for you.
The Vanishing (1988) (More thriller then horror, but a great french suspense movie with disturbing nature, before the 6th sense this was the one that could be most ruined if someone told you ending....dont ask just watch)
[REC] (2007) Really good Spanish horror film more in the zombie camp. Jump scares done well...the best non zombie, zombie film.
I dunno just some I like.....