- Make (Years In Operation) – Plant
-
- Models
- Halliday (1905-1922) – Mansfield, OH
- Six
- Hamlin-Holmes (1919-1930) – Chicago, IL
- No models named
- Handley-Knight (1921-1923) – Kalamazoo, MI
- No models named
- Hanover (1921-1927) – Pennsylvania
- Light Car
- Hanson (1918-1925) – Atlanta, GA
- Six
- Little Six
- Special Six
- Harris (1923) – Menasha, WI
- Six
- Harroun (1917-1922) – Wayne, MI
- A-1
- 18
- AA-2
- Harvard (1915-1921) – New York, NY
- Four
- Hatfield (1916-1924) – Sidney, NY
- A-42
- 55
- Haynes (1898-1925) – Kokomo, IN
- 45
- 46
- 47
- 48
- 55
- 75
- 57
- 77
- 60
- H. C. S. (1920-1925) – Indianapolis, IN
- II
- III
- IV
- VI
- Henney (1921-1931) – Freeport, IL
- No models named
- Hertz (1926-1927) – Chicago, IL
- D-1
- Highlander (1919-1922) – Kansas City, MO
- Six
- Hilton (1920-1921) – Riverton, NJ
- Four
- Hoffman (1931) – Detroit, MI
- No models named
- Hollier (1915-1921) – Jackson, MI
- Six
- Holmes 1918-1923) – Canton, OH
- I
- 4
- Holtom (1934) – New York, NY
- No models named
- Howard (1925-1929) – Detroit, MI
- No models named
- Hudson (1910-1942) – Detroit, MI
- Super Six
- Super O
- O
- S
- R
- L
- T
- U
- 815
- E
- LT
- LT5
- LLD
- LU
- HHU
- HU
- HTL
- GH
- HT
- HUL
- 63 to 67
- 73 to 77
- 81 to 85
- 87
- 89 to 93
- 40T
- 40P
- 41
- 43
- 44
- 45
- 47
- 10T
- 10P
- 11
- 12
- 14
- 15
- 17
- 22
- 24
- 25
- 27
- 20P
- 21
- Huffman (1920-1925) – Elkhart, IN
- R
- 7-R
- K
- L
- Hungerford Rocket (1929) – Elmira, NY
- No models named
- Hupmobile (1909-1941) – Detroit, MI
- R-1 to R-15
- E-1
- A-1
- E-2
- A
- E-3
- M
- E-4
- 5
- C
- H
- U
- L
- C
- S-214
- B-216
- L-218
- C-221
- F-222
- H-225
- I-226
- V-237
- K-321
- kk-321-A
- F-322
- I-326
- 417-W
- KK-421A
- K-421
- 421-J
- F-442
- I-426
- 427-T
- 517-W
- 518-D
- 521-J
- 521-O
- 527-T
- 618-D
- 618-G
- 621-N
- 621-O
- 822-ES
- 822-E
- 825-H
- R
- E
- H
- Skylark
- 115-R
- Models
