| Episode # | Title | Airdate |
|---|---|---|
| Season 1 | ||
| 1 | The Great Debate | 9/9/1975 |
| 2 | Basket Case | 9/16/1975 |
| 3 | Welcome Back (Pilot) | 9/23/1975 |
| 4 | Whodunit? | 9/30/1975 |
| 5 | The Election | 10/7/1975 |
| 6 | No More Mister Nice Guy | 10/14/1975 |
| 7 | Classroom Marriage | 10/21/1975 |
| 8 | One of Our Sweathogs Is Missing | 10/28/1975 |
| 9 | Mr. Kotter, Teacher | 11/4/1975 |
| 10 | The Reunion | 11/18/1975 |
| 11 | Barbarino's Girl | 11/25/1975 |
| 12 | California Dreamin' | 12/2/1975 |
| 13 | Arrividerci, Arnold | 12/16/1975 |
| 14 | The Longest Weekend | 1/6/1976 |
| 15 | The Sit-In | 1/13/1976 |
| 16 | Follow The Leader (1) | 1/20/1976 |
| 17 | Follow The Leader (2) | 1/22/1976 |
| 18 | Dr. Epstein, I Presume | 1/29/1976 |
| 19 | One Flu Over The Cuckoo's Nest | 2/5/1976 |
| 20 | The Telethon | 2/12/1976 |
| 21 | Kotter Makes Good | 2/19/1976 |
| 22 | Father Vinnie | 2/26/1976 |
| Season 2 | ||
| 23 | Career Day | 9/23/1976 |
| 24 | Inherit The Halibut | 9/30/1976 |
| 25 | Sweatside Story | 10/7/1976 |
| 26 | The Fight | 10/21/1976 |
| 27 | The Museum | 10/28/1976 |
| 28 | Gabe Under Pressure | 11/4/1976 |
| 29 | Sweathog, Nebraska Style | 11/11/1976 |
| 30 | Sadie Hawkins Day | 11/18/1976 |
| 31 | Hello, Ms. Chips | 12/2/1976 |
| 32 | Horshack vs. Carvelli | 12/9/1976 |
| 33 | Sweathog Clinic for the Cure of Smoking | 12/16/1976 |
| 34 | Hark, the Sweatkings | 12/23/1976 |
| 35 | A Love Story | 12/30/1976 |
| 36 | Caruso's Way | 1/6/1977 |
| 37 | Sweatgate Scandal | 1/13/1977 |
| 38 | Kotter and Son | 1/20/1977 |
| 39 | Chicken a la Kotter | 1/27/1977 |
| 40 | Has Anyone Seen Arnold? (1) | 2/3/1977 |
| 41 | There Goes Number 5 (2) | 2/3/1977 |
| 42 | The Littlest Sweathog | 2/10/1977 |
| 43 | Radio Free Freddie | 2/17/1977 |
| 44 | I'm Having Their Baby | 2/24/1977 |
| 45 | I Wonder Who's Kissing Gabe Now? | 3/3/1977 |
| Season 3 | ||
| 46 | Sweathogs Back-to-School Special | 9/10/1977 |
| 47 | And Baby Makes Four (1) | 9/15/1977 |
| 48 | And Baby Makes Four (2) | 9/15/1977 |
| 49 | And Baby Makes Four (3) | 9/22/1977 |
| 50 | Brother, Can You Spare a Million? | 9/29/1977 |
| 51 | Just Testing | 10/6/1977 |
| 52 | The Deprogramming of Arnold Horshack | 10/13/1977 |
| 53 | What a Move | 10/20/1977 |
| 54 | A Novel Idea | 10/27/1977 |
| 55 | Barbarino in Love (1) | 11/3/1977 |
| 56 | Barbarino in Love (2) | 11/10/1977 |
| 57 | Kotter for Vice Principal | 11/17/1977 |
| 58 | Swine and Punishment | 11/24/1977 |
| 59 | Epstein's Madonna | 12/8/1977 |
| 60 | Sweathog Christmas Special | 12/15/1977 |
| 61 | Sweatwork | 12/22/1977 |
| 62 | Meet Your New Teacher: Batteries Not Included | 1/5/1978 |
| 63 | Angie | 1/12/1978 |
| 64 | Epstein's Term Paper | 1/19/1978 |
| 65 | There's No Business Like Show Business (1) | 1/26/1978 |
| 66 | There's No Business Like Show Business (2) | 2/2/1978 |
| 67 | What Goes Up | 2/9/1978 |
| 68 | Goodbye, Mr. Kripps | 2/16/1978 |
| 69 | Horshack and the Madame X | 2/23/1978 |
| 70 | The Kiss | 3/9/1978 |
| 71 | The Return of Hotsy Totsy | 5/11/1978 |
| 72 | Class Encounter of the Carvelli Kind | 5/18/1978 |
| Season 4 | ||
| 73 | The Drop-Ins (1) | 9/11/1978 |
| 74 | The Drop-Ins (2) | 9/11/1978 |
| 75 | Don't Come Up and See Me Sometime | 9/25/1978 |
| 76 | Once Upon a Ledge | 10/2/1978 |
| 77 | The Sweatmobile | 10/9/1978 |
| 78 | Beau's Jest | 10/16/1978 |
| 79 | Barbarino's Boo-Boo | 10/21/1978 |
| 80 | X-Rated Education | 10/28/1978 |
| 81 | The Barbarino Blues | 11/3/1978 |
| 82 | Washington's Clone | 11/11/1978 |
| 83 | Frog Day Afternoon | 11/25/1978 |
| 84 | A Little Fright Music | 12/2/1978 |
| 85 | A Winter's Coat Tale | 12/16/1978 |
| 86 | Bride and Gloom | 1/13/1979 |
| 87 | Barbarino's Baby | 2/3/1979 |
| 88 | The Goodbye Guy | 2/10/1979 |
| 89 | Come Back, Little Arnold | 2/24/1979 |
| 90 | The Sweat Smell of Success | 3/3/1979 |
| 91 | The Gang Show | 3/17/1979 |
| 92 | Oo, Oo, I Do (1) | 5/25/1979 |
| 93 | Oo, Oo, I Do (2) | 5/25/1979 |
| 94 | I'm Okay, But You're Not | 6/1/1979 |
| 95 | The Breadwinners | 6/8/1979 |
Welcome Back, Kotter Episode List
Season 1 | Season 2 | Season 3 | Season 4
