- January 1, 1980: (The first comic strip of 1980, and the 1980s)
- January 2, 1980:
- January 3, 1980:
- January 4, 1980: (The same concept is used in Garfield on the Town)
- January 5, 1980:
- January 6, 1980:
- January 7, 1980:
- January 8, 1980:
- January 9, 1980:
- January 10, 1980:
- January 11, 1980:
- January 12, 1980:
- January 13, 1980:
- January 14, 1980: (The start of a storyline about Garfield getting a cold)
- January 15, 1980:
- January 16, 1980:
- January 17, 1980:
- January 18, 1980:
- January 19, 1980: (The end of a storyline about Garfield getting a cold)
- January 20, 1980:
- January 21, 1980:
- January 22, 1980:
- January 23, 1980:
- January 24, 1980:
- January 25, 1980:
- January 26, 1980:
- January 27, 1980:
- January 28, 1980: (The start of a "Vet week")
- January 29, 1980:
- January 30, 1980:
- January 31, 1980:
| ← Garfield, December 1979 | Garfield, February 1980 → |