Tournament Record - Ian O'Mahony In United States Amateur Championship
| Played | Winner | Final | Semi-final | Quarter-final | Last 16 | Last 32 | Prize Money | Centuries |
|---|---|---|---|---|---|---|---|---|
| 4 | 0 | 0 | 0 | 0 | 0 | 0 | 234 | 0 |
| Tournament | Finish | Prize Money (GBP) |
|---|---|---|
 2021 United States Amateur Championship |
Last 16 | 0 |
| 2017 United States Amateur Championship |
Quarter-final | 234 |
| 2016 United States Amateur Championship |
Last 12 | 0 |
| 2015 United States Amateur Championship |
Quarter-final | 0 |