Sean O’Malley has been in the UFC since December 1, 2017, so as of early 2026 he’s been in the promotion for a little over 8 years.

How long he’s been in the UFC

  • O’Malley made his official UFC debut on December 1, 2017, at The Ultimate Fighter 26 Finale against Terrion Ware, winning by unanimous decision.
  • Counting from December 2017 to January 2026, that puts his UFC tenure at about 8 years and 1–2 months.

So if you’re just looking for a quick answer to “how long has Sean O’Malley been in the UFC,” the answer is: a bit over eight years as of now.

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