Boulder, Montana
3U9 Boulder
Boulder (3U9) is a non-towered, public-use airport in Boulder, Montana, at 4,968 ft MSL. Its runway is 11/29 (3,675 by 72 ft, turf). CTAF 122.9.
FAA NASR data effective Oct 29, 2026. Not for navigation; verify with current FAA charts and the Chart Supplement.
Airport
At a glance
- Identifiers
- FAA 3U9
- Location
- Boulder, Montana (Jefferson County). 2 NM S of the city center
- Elevation
- 4,968 ft MSL
- Position
- 46.2117° N, 112.1076° W
- Control tower
- No, non-towered
- Sectional chart
- Great Falls
- Magnetic variation
- 17° E (1985)
- Ownership
- Publicly owned, open to the public
- Attendance
- Unattended
1 runway
Runways
| Runway | Length × width | Surface | Edge lights |
|---|---|---|---|
| 11/29 | 3,675 × 72 ft | Turf, fair condition | Not listed |
Runway ends and traffic pattern
| End | Pattern | Glide slope lights | Instrument | Displaced threshold | Landing distance |
|---|---|---|---|---|---|
| 11 | Left traffic | None listed | None listed | None listed | Not listed |
| 29 | Not stated | None listed | None listed | None listed | Not listed |
VHF
Frequencies
- CTAF
- 122.9
Before you go
Brief 3U9 in Ascent EFB.
Current weather, NOTAMs and the airport diagram for Boulder, in the app on iPhone and iPad.
Not for navigation. Verify with current FAA charts and the Chart Supplement before flight.
Source: FAA NASR 28-day subscription, cycle effective Oct 29, 2026. Airport data changes every 28 days and NOTAMs can override it at any time.