1. Dawn of the Dead (1978)
2. Jaws
3. Alien
4. Haute Tension
5. The Exorcist
6. The Beast Within (1982)
7. The Descent
8. The Hitcher (1986)
9. Let the Right One In
10. Sputnik (2020)

HM:
The Thing (1982)
The Fly (1986)
Invasion of the Body Snatchers (1976)
Martyrs (2008)
Rogue (2007)
Eden Lake

Halloween
The Exorcist
The Shining
The Texas Chainsaw Massacre
The Fog
The Orphanage
Insidious
The Thing
Dawn of the Dead (2004)
The Changeling

Jaws is my favorite movie but I don’t really consider it “Horror.”

1 ) “The Exorcist”
2 ) “Hereditary”
3 ) “Alien”
4 ) “Insidious”
5 ) “The Silence of the Lambs”
6 ) “The Strangers”
7 ) “The Omen"
8 ) “It”
9 ) “Rosemary’s Baby”
10 ) “1408”

Hope some of these are considered "horror". Scary, yes.

I tried to make a list. But after looking through my collection, I realized I'd be up half the night trying to whittle it down to 10.

There's maybe 3-4 movies at the top. But at least 50 movies would be tied for the remaining spots.

How’s about my favorite from each decade?

1920s: Nosferatu
1930s: Dr. Jekyll & Mr. Hyde
1940s: The Body Snatcher
1950s: Gojira
1960s: Black Sabbath (The Bava Cut)
1970s: The Texas Chainsaw Massacre
1980s: An American Werewolf in London
1990s: The Addiction
2000s: The House Of The Devil
2010s: You’re Next

Off the top of my head, my gut says:

1) Dawn of the Dead
2) Halloween
3) The Shining
4) Abbott and Costello Meet Frankenstein
5) The Return of the Living Dead
6) Fright Night

This is the point I start having to thinking harder.

7) Night of the Living Dead
8) The Exorcist
9) The Texas Chainsaw Massacre
10) The Bride of Frankenstein

I know my list is pretty boring, but I'm using the definition of favourite being "a movie can't bear the thought of never seeing again". As much as I value movies like A Nightmare On Elm Street, or An American Werewolf In London, if I never saw them again I wouldn't really notice.

You son of a bitch, I’m in!

1920s: The Phantom Carriage
1930s: Vampyr
1940s: The Uninvited
1950s: The House on Haunted Hill
1960s: Psycho
1970s: Halloween
1980s: The Fog
1990s: From Dusk Til Dawn
2000s: The Orphanage
2010s: Insidious

Choosing for the 70s and 80s was like Sophie’s Choice.

Ditto.

Alien
Evil Dead
Poltergeist
The Exorcist

the rest is kind-of a free-for-all with honorable mention going to Cronenberg's The Fly, and Let's Scare Jessica To Death

The Devil's Backbone
The Thing (1982)
The Exorcist
The Fly (1986)
Texas Chainsaw Massacre (1974)
Psycho (1960)
Freaks (1932)
Ringu
Night of the Living Dead
Halloween (1978)
Alien
Hereditary
Silence of the Lambs
Dracula
Jaws
The Evil Dead (1981)
Dawn of the Dead (1978)

1 - the Thing
2 - Dawn of the Dead
3 - Alien
4 - Halloween
5 - Creature From The Black Lagoon
6 - the Exorcist
7 - the Fog
8 - Night Of The Living Dead
9 - Jaws
10 - Friday the 13th part 2

1. The Thing
2. From Dusk Till Dawn
3. Alien
4. The Frighteners
5. Ravenous
6. The Ring (2002)
7. Event Horizon
8. The Mist
9. 30 Days of Night
10. Get Out

Two groups of five films each, the first consists of those about monstrous human beings, with no supernatural elements whatsoever. These are the most horrifying and unsettling to me.
The second consists of more traditional horror genre elements.

Shadow of a Doubt (1943) Alfred Hitchcock

In a Lonely Place (1950) Nicholas Ray

The Bad Seed (1956) Mervyn Leroy

Whatever Happened to Baby Jane? (1962) Robert Aldrich

Hush, Hush, Sweet Charlotte (1965) Robert Aldrich



Dr. Jekyll and Mr. Hyde (1932) Ruben Mamoulian

Island of Lost Souls (1933) Erle C. Kenton

The Horror of Dracula (1958) Terence Fisher

Psycho (1960) Alfred Hitchcock

Frankenstein Must Be Destroyed (1970) Terence Fisher

1. Halloween (1978)
2. The Exorcist
3. The Thing (1982)
4. The Cell
5. Get Out
6. 28 Days Later
7. Poltergeist (1982)
8. Dawn of the Dead (2004, you read that right!)
9. Bram Stoker's Dracula
10. Hausu

I agree with GoldenJCJ . I could definitely put Jaws at the top, but doesn't feel right.

1. Carrie
2. Suspiria
3. Dawn of the Dead
4. The Texas Chain Saw Massacre
5. A Tale of Two Sisters
6. Rosemary's Baby
7. The Thing
8. The Blair Witch Project
9. Night of the Living Dead
10. Hell Night

All original versions, except The Thing ('82). The order is just what I thought of as I typed, with the exception of Carrie, easily the best horror film ever made.

Evil Dead 2
Evil Dead
Alien
The Texas Chainsaw Massacre
Jaws
The Thing
Halloween
Night Of The Living Dead
Fright Night
The Blob

The Exorcist
Eyes Without a Face
Rosemary's Baby
Nosferatu
Suspiria
Night of the Living Dead
The Texas Chainsaw Massacre
Kairo (Pulse)
Psycho
Don't Look Now

No way I can put together a whole list, but if Let Me In is considered horror then that is without a doubt my #1 as it is one of my favorite movies period.

These are my top 3, I really can't get a top 10, too many choices:

Rosemary's Baby
The Exorcist
Dead of Night

I’m not a fan of ALL of Carpenter’s films but you have to admit, the dude was killing it in the late 70s and early 80s!

This could change from day to day:

1. Halloween (1978)
2. Silence of the Lambs (1991)
3. Se7en (1995)
4. Scream (1996)
5. Psycho (1960)
6. Return of the Living Dead (1985)
7. [REC] (2007)
8. The Conjuring (2013)
9. Poltergeist (1982)
10. A Nightmare on Elm Street (1984)

In no particular order...

Leprechaun
Leprechaun 2
Leprechaun 3
Leprechaun 4: In Space
Leprechaun in the Hood
Leprechaun Back 2 tha Hood
Leprechaun Origins
Leprechaun Returns
Leprechaun Electric Boogaloo
Haute Leprechaun Tension

^ I know you’re joking but the most surprising thing about that post is that it made me double check how many Leprechaun movies there are. Damned if I’m not shocked that there are 8 freaking Leprechaun films!

I would have bet money that there were only like three of four, tops.

I've only not seen two of them, but I hope to correct that soon.
For what it's worth, Returns has some pretty great practical gore. It's worth watching, but just... Don't expect too much in terms of plot or acting.
I was kind of obsessed with L3 when it was available on VHS. Watched it way more times than any normal person should

Seriously? The best horror film ever made??