| Atari 400/800 cass. |  Adventure of the Month #8: Winsloe Mansion Adventure | 1982 | SoftSide Publications, Inc. |
| Atari 400/800 cass. | Adventure of the Month #9: Klondike Adventure | 1982 | SoftSide Publications, Inc. |
| Atari 400/800 cass. | Adventure! Model CS-7009 | 1980 | Creative Computing Soft. |
| Atari 400/800 cass. | Adventures #10~#12 Model 050-0130 | 198? | Adventure International |
| Atari 400/800 cass. | Adventures #1~#3 Model 050-0010 | 198? | Adventure International |
| Atari 400/800 cass. | Adventures #4~#6 Model 050-0011 | 198? | Adventure International |
| Atari 400/800 cass. | Adventures #7~#9 Model 050-0012 | 198? | Adventure International |
| Atari 400/800 cass. | Air Rescue | 1991 | Atlantis Soft. |
| Atari 400/800 cass. | Air Traffic Controller Model CS-7004 | 1981 | Creative Computing Soft. |
| Atari 400/800 cass. | Air-Raid! Model APX-10187 | 1982 | APX Atari Program Exchange |
| Atari 400/800 cass. | Airstrike II | 1983 | English Soft. |
| Atari 400/800 cass. | Airwolf | 1985 | Elite Systems, Ltd. |
| Atari 400/800 cass. | Alchemia | 1993 | Mirage |
| Atari 400/800 cass. | Alien Hell | 1981 | Syncro |
| Atari 400/800 cass. | All Star Baseball Model 6401 | 1979 | Image Computer Products |
| Atari 400/800 cass. | Alley Cat | 1986 | Americana Soft. |
| Atari 400/800 cass. | Amaurote | 1987 | Mastertronic, Ltd. UK 012967 |
| Atari 400/800 cass. | Arcade Classics: Seawolf II + Gun Fight Model 714C P | 1983 | Epyx, Inc. Redwood City, CA, USA |
| Atari 400/800 cass. | Arcade Classics: Starfire + Fire One Model 734C P | 1983 | Epyx, Inc. Redwood City, CA, USA |
| Atari 400/800 cass. | Arcade Fruit Machine Model F220 | 1990 | Zeppelin Games |
| Atari 400/800 cass. | Arkanoid Model 110849 P | 1987 | Imagine Soft. Ocean Group 13156 |
| Atari 400/800 cass. | Asteroid Miners | 1982 | MMG Micro Soft. |
| Atari 400/800 cass. | Astro-Droid | 1987 | Red Rat Soft. |
| Atari 400/800 cass. | Astro-Quotes - Game #1 | 1980 | PDI Program Design, Inc. |
| Atari 400/800 cass. | Astro-Quotes - Game #2 | 1980 | PDI Program Design, Inc. |
| Atari 400/800 cass. | Astro-Quotes - Game #3 | 1980 | PDI Program Design, Inc. |
| Atari 400/800 cass. | Astron IV | 1982 | Syncro |
| Atari 400/800 cass. | Asylum | 1983 | Screenplay |
| Atari 400/800 cass. | Atari Smash Hits Vol. 1 | 1985 | English Soft. |
| Atari 400/800 cass. | Atari Smash Hits Vol. 2 | 1985 | English Soft. |
| Atari 400/800 cass. | Atari Smash Hits Vol. 3 | 1985 | English Soft. |
| Atari 400/800 cass. | Atari Smash Hits Vol. 4 Model 082 | 1985 | English Soft. |
| Atari 400/800 cass. | Atari Smash Hits Vol. 5 Model 167 | 1986 | English Soft. |
| Atari 400/800 cass. | Atari Smash Hits Vol. 6 Model 181 | 1986 | English Soft. |
| Atari 400/800 cass. | Atari Smash Hits Vol. 7 Model 259 | 1987 | English Soft. |
| Atari 400/800 cass. | Atlas of Canada Model APX-10093 | 1982 | APX Atari Program Exchange |
| Atari 400/800 cass. | Attack at EP-CYG-4 | 1982 | Bram, Inc. |
| Atari 400/800 cass. | Attack of the Mutant Camels | 1984 | Llamasoft |
| Atari 400/800 cass. | Attank! Model APX-10072 | 1981 | APX Atari Program Exchange |
| Atari 400/800 cass. | Attaque ! Model APX 10072 | 198? | Atari PECF Creteil, France |
