| 2026-08-08 | UFC Fight Night: Gamrot vs. Salkilld | Lightweight | Carlos Diego Ferreira def. Billy Quarantillo | Decision (unanimous) (30–27, 30–27, 30–27) | 3 | 5:00 |
| 2024-12-14 | UFC on ESPN: Covington vs. Buckley | Featherweight | Cub Swanson def. Billy Quarantillo | KO (punch) | 3 | 1:36 |
| 2024-03-23 | UFC on ESPN: Ribas vs. Namajunas | Featherweight | Youssef Zalal def. Billy Quarantillo | Submission (rear-naked choke) | 2 | 1:50 |
| 2023-08-05 | UFC on ESPN: Sandhagen vs. Font | Featherweight | Billy Quarantillo def. Damon Jackson | Decision (unanimous) (29–28, 29–28, 29–28) | 3 | 5:00 |
| 2023-04-15 | UFC on ESPN: Holloway vs. Allen | Featherweight | Edson Barboza def. Billy Quarantillo | KO (knee) | 1 | 2:37 |
| 2022-12-10 | UFC 282: Błachowicz vs. Ankalaev | Featherweight | Billy Quarantillo def. Alexander Hernandez | TKO (knees and punches) | 2 | 4:30 |
| 2021-11-06 | UFC 268: Usman vs. Covington 2 | Featherweight | Shane Burgos def. Billy Quarantillo | Decision (unanimous) (29–28, 29–28, 29–28) | 3 | 5:00 |
| 2021-07-17 | UFC on ESPN: Makhachev vs. Moisés | Featherweight | Billy Quarantillo def. Gabriel Benítez | TKO (punches) | 3 | 3:40 |
| 2020-12-12 | UFC 256: Figueiredo vs. Moreno | Featherweight | Gavin Tucker def. Billy Quarantillo | Decision (unanimous) (30–27, 30–27, 30–27) | 3 | 5:00 |
| 2020-09-12 | UFC Fight Night: Waterson vs. Hill | Featherweight | Billy Quarantillo def. Kyle Nelson | KO (punch) | 3 | 0:07 |
| 2020-05-30 | UFC on ESPN: Woodley vs. Burns | Catchweight | Billy Quarantillo def. Spike Carlyle | Decision (unanimous) (29–28, 29–28, 29–28) | 3 | 5:00 |
| 2019-12-07 | UFC on ESPN: Overeem vs. Rozenstruik | Featherweight | Billy Quarantillo def. Jacob Kilburn | Submission (triangle choke) | 2 | 3:18 |