| ITF M25 - Rancho Santa Fe | 01/15 17:30 | 25 | Collin Altamirano v Lucas Gomez | 6-0,2-6,6-2 | |
| ITF M25 Los Angeles | 01/10 18:00 | 27 | [366] Alexander Ritschard v Collin Altamirano [340] | 6-1,3-6,6-3 | |
| ITF M25 Los Angeles | 01/09 20:45 | 26 | Alex Rybakov v Collin Altamirano | 6-3,3-6,4-6 | |
| ITF M25 Los Angeles | 01/07 20:50 | 25 | Roy Smith v Collin Altamirano | 7-6,1-6,4-6 | |
| ITF M15 - Austin | 11/24 16:50 | 29 | Collin Altamirano v Jacob Fearnley | 4-6,6-4,6-4 | |
| ITF M15 - Austin | 11/23 18:30 | 28 | [369] Collin Altamirano v Ruan Roelofse [231] | 6-4,4-6,6-2 | |
| ITF M15 - Austin | 11/22 17:00 | 27 | Collin Altamirano v Hady Habib | 6-3,6-1 | |
| ITF M15 - Austin | 11/21 18:25 | 26 | Collin Altamirano v Preston Brown | 6-2,6-0 | |
| ITF M15 - Austin | 11/20 18:50 | 25 | Collin Altamirano v Michael Shabaz | 7-5,6-2 | |
| Challenger Houston | 11/13 17:50 | 25 | [390] Collin Altamirano v Adrian Menendez-Maceiras [236] | 4-6,0-6 | |
| Challenger Houston | 11/11 21:10 | 24 | Gage Brymer v Collin Altamirano | 2-6,6-7 | |
| ITF M25 - Malibu | 11/09 22:40 | 28 | [395] Collin Altamirano v Daniel Altmaier [364] | 6-7,6-2,5-7 | |
| ITF M25 - Malibu | 11/08 18:00 | 27 | [429] Evan Song v Collin Altamirano [395] | 3-6,4-6 | |
| ITF M25 - Malibu | 11/07 19:35 | 26 | [399] Austin Rapp v Collin Altamirano [395] | 1-6,3-6 | |
| ITF M25 - Malibu | 11/06 00:40 | 25 | Isaiah Strode v Collin Altamirano | 2-6,5-7 | |
| Challenger Las Vegas | 10/15 17:30 | 24 | [373] Collin Altamirano v Kevin King [330] | 3-6,5-7 | |
| Challenger Fairfield | 10/07 18:00 | 24 | Brandon Holt v Collin Altamirano | 6-2,6-2 | |
| Challenger Tiburon | 09/23 20:30 | 24 | [292] JC Aragone v Collin Altamirano [358] | 6-2,7-6 | |
| Challenger Kaohsiung | 09/16 09:00 | 24 | [319] Teymuraz Gabashvili v Collin Altamirano [396] | 6-3,5-7,6-4 | |
| Challenger Shanghai | 09/13 04:35 | 27 | [438] Di Wu v Collin Altamirano [396] | 6-4,6-0 | |
| Challenger Shanghai | 09/12 04:20 | 26 | [396] Collin Altamirano v Tatsuma Ito [139] | 6-3,7-6 | |
| Challenger Shanghai | 09/10 04:00 | 25 | [256] Aleksandar Vukic v Collin Altamirano [396] | 4-6,6-7 | |
| Challenger Shanghai | 09/09 05:45 | 24 | [316] Collin Altamirano v Xin Gao [372] | 6-1,6-1 | |
| Challenger Jinan | 09/02 04:30 | 24 | [476] Di Wu v Collin Altamirano [316] | 6-4,6-4 | |
| Challenger Lexington | 07/31 19:20 | 25 | [274] Collin Altamirano v Roy Smith [314] | 4-6,7-6,2-6 | |
| Challenger Binghamton | 07/25 15:55 | 26 | [169] Dudi Sela v Collin Altamirano [283] | 6-4,7-5 | |
| Challenger Binghamton | 07/24 14:00 | 25 | [283] Collin Altamirano v Jeffrey John Wolf [261] | 6-2,7-5 | |
| Challenger Binghamton | 07/23 16:25 | 24 | [338] Lloyd Glasspool v Collin Altamirano [283] | 1-6,6-7 | |
| Challenger Gatineau | 07/15 17:35 | 24 | [284] Collin Altamirano v Brandon Holt [497] | 1-6,6-7 | |
| Challenger Winnetka | 07/11 17:25 | 26 | [115] Denis Istomin v Collin Altamirano [268] | 6-3,6-0 |