National Wildlife Refuge · Montana · FWS Region 6

Grass Lake National Wildlife Refuge Hunting & Fishing Guide 2026–27

Located in Stillwater County, Montana, Grass Lake National Wildlife Refuge is managed by the U.S. Fish and Wildlife Service, with about 3,394 acres of land owned in fee by the U.S. Fish and Wildlife Service. For the 2026–2027 season the refuge has 2 mapped hunt units: 1 open under general rules and 1 closed, covering about 1,712 huntable acres.

1 open unit1 closed
View hunt map Directions Official website ↗
2hunt units
1.7Khuntable acres
3.4KFWS-owned acres
5game categories

Grass Lake NWR hunt unit map

Hunt units are colored by 2026–2027 status. Toggle layers for FWS-owned land, the approved refuge boundary and private easements. Use satellite imagery to scout marshes, timber edges and access points.

Loading interactive map…
OpenSpecial regulationsClosedFWS-owned landWPA (public)Refuge boundaryEasement (private) Tip: switch to Satellite or USGS Topo in the layer menu · click the map for GPS coordinates
Take it into the field: KML (Google Earth / onX) GPX waypoints GeoJSON

Hunting at Grass Lake NWR

Permitted hunting categories are big game, waterfowl, wild turkey, upland birds, and migratory birds, subject to state seasons and refuge-specific rules.

Big GameWhite-tailed and mule deer, elk, pronghorn, moose, bear and other large mammalsWaterfowlDucks, geese, brant, swans (where legal) and cootsWild TurkeySpring and fall wild turkeyUpland BirdsPheasant, quail, grouse, prairie chicken and partridgeMigratory BirdsMourning dove, woodcock, snipe, rails, gallinules and sandhill crane

Categories are those listed by USFWS for this station; exact species, seasons and bag limits follow Montana regulations plus refuge-specific rules.

Hunt units (2)

Acreage by status
Open: 1,712 (50%)Closed: 1,682 (50%)1.7Khuntable acres
  • Open1,712 ac 50%
  • Closed1,682 ac 50%
Units by size (acres)
Open Unit
1,712 ac
Closed Unit
1,682 ac
UnitStatusAcresPermitDetails
Open Unit
Show on map · Directions		 Open 1,712 —
Closed Unit
Show on map · Directions		 Closed 1,682 —

Grass Lake NWR by the numbers

With about 1,712 huntable acres, Grass Lake NWR ranks #18 of 23 refuges and stations with mapped hunting land in Montana and #335 of 420 nationwide. Roughly 50% of the acreage inside its mapped hunt units is open to hunting in some form.

The largest huntable unit is Open Unit (1,712 acres).

1 unit totaling 1,682 acres is closed to hunting (Closed Unit). Closed areas often serve as sanctuaries — learn their boundaries before you set up nearby.

5 Waterfowl Production Areas lie within 35 miles; the closest is Hailstone WPA (1,766 acres, 5 miles NW).

When to hunt Grass Lake NWR

Typical U.S. season windows for the game categories offered here. Montana sets the exact dates, and refuges often open fewer days than the statewide season — use this to plan scouting, then confirm the 2026–2027 dates in the state regulations and the refuge hunt brochure.

Typical season windows — Big Game, Waterfowl, Wild Turkey, Upland Birds, Migratory Birds
AugSepOctNovDecJanFebMarAprMayJun
🦌 Big Game
Archery deerFirearm deer
🦆 Waterfowl
Early teal & gooseRegular duck & goose
🦃 Wild Turkey
Spring gobblerFall (some states)
🐦 Upland Birds
Pheasant, quail, grouse
🕊️ Migratory Birds
Dove (Sept. 1 opener)Woodcock & snipeLate dove split

Permits & licenses

Refuge permit

Not listed

USFWS does not list a separate refuge permit for this station. Specific units or hunts (e.g. quota deer hunts) may still require one — check the hunt brochure.

You'll also need

  • A valid Montana hunting license and any required tags or stamps — Montana Fish, Wildlife & Parks
  • Federal Duck Stamp (waterfowl hunters 16+) and HIP certification for migratory birds
  • Non-toxic shot for waterfowl (federal requirement)
  • Hunter education certification where your state requires it
  • The current refuge hunt brochure / regulations (often must be signed and carried)

Fishing at Grass Lake NWR

USFWS does not list fishing opportunities for Grass Lake NWR.

How to get to Grass Lake NWR

Navigate

Destination: Grass Lake National Wildlife Refuge (FWS reference point)

Google Maps Apple Maps Waze
Decimal
45.94199, -109.11190
DMS
45°56′31.2″N 109°06′42.8″W

Download for GPS / onX / Google Earth:KMLGPX

Nearest towns

  • Billings, MT31 mi W of town
  • Lewistown, MT79 mi S of town
  • Bozeman, MT95 mi E of town
  • Cody, WY98 mi N of town

Closest airports

  • BIL Billings Logan29 mi
  • BZN Bozeman Yellowstone99 mi

Straight-line distances. Driving routes are longer; many refuge roads are gravel and may close seasonally.

The navigation point is the station reference location published by USFWS — often the headquarters or main entrance. For a specific hunt unit, open its page or click it on the map for coordinates and parking planning.

Sunrise, sunset & shooting hours

Today at Grass Lake NWR

Legal light*–
Sunrise–
Sunset–

*½ hour before sunrise — the standard federal shooting-hour start for migratory game birds. Times in Denver local time.

Full season calculator →

2026–2027 season sun table

DateShooting lightSunriseSunsetDaylight
Tue, Sep 1, 20266:06 AM6:36 AM7:57 PM13h 22m
Tue, Sep 15, 20266:23 AM6:53 AM7:30 PM12h 37m
Thu, Oct 1, 20266:43 AM7:13 AM6:58 PM11h 46m
Thu, Oct 15, 20267:01 AM7:31 AM6:32 PM11h 01m
Sun, Nov 1, 20266:25 AM6:55 AM5:04 PM10h 09m
Sun, Nov 15, 20266:45 AM7:15 AM4:46 PM9h 31m
Tue, Dec 1, 20267:07 AM7:37 AM4:34 PM8h 57m
Tue, Dec 15, 20267:21 AM7:51 AM4:32 PM8h 41m
Fri, Jan 1, 20277:27 AM7:57 AM4:40 PM8h 43m
Fri, Jan 15, 20277:24 AM7:54 AM4:55 PM9h 01m
Mon, Feb 1, 20277:09 AM7:39 AM5:19 PM9h 40m

Computed for 45.942, -109.112 (MDT / DST-aware). Check state rules — big game hours vary.

7-day hunting weather

Loading National Weather Service forecast…

Forecast from the National Weather Service. Wind direction matters — plan your approach downwind of where game beds.

Guides for hunting Grass Lake NWR

Deer Hunting on National Wildlife Refuges: Quota Hunts, Archery Units and Stand Rules

How refuge deer hunts work — lotteries and quota permits, archery-only and muzzleloader units, tree-stand rules…

Public-Land Duck Hunting on National Wildlife Refuges: Tactics That Work

How to find ducks, beat the crowds and set up on refuge marshes and WPAs — scouting, timing, small decoy spreads for…

Federal Duck Stamp Explained: Who Needs One, Where to Buy It and Where the Money Goes

Everything waterfowl hunters need to know about the Federal Duck Stamp — who must carry it, signing rules, the…

Nontoxic Shot Guide for Refuge and WPA Hunters

Why lead shot is banned for waterfowl, which nontoxic loads are approved, how steel, bismuth and tungsten compare, and…

Turkey Hunting on Wildlife Refuges: Lotteries, Pressured Birds and Safety

How spring and fall turkey hunts work on National Wildlife Refuges, how to scout and call public-land gobblers, and…

Pheasant and Upland Bird Hunting on Waterfowl Production Areas

Why WPAs are some of the best walk-in pheasant ground in the Midwest, how to hunt them early and late in the season…

Grass Lake NWR FAQ

Is hunting allowed at Grass Lake NWR?

Yes. Grass Lake National Wildlife Refuge offers hunting in 1 unit (1,712 acres) during 2026–2027 for big game, waterfowl, wild turkey, upland birds, and migratory birds. Seasons follow state regulations plus refuge-specific rules in 50 CFR Part 32.

Do I need a permit to hunt Grass Lake NWR?

FWS data does not list a separate refuge hunting permit for Grass Lake NWR. You still need a valid state license, any required state tags or stamps, and (for waterfowl hunters 16+) a Federal Duck Stamp.

Where is Grass Lake NWR located?

Grass Lake National Wildlife Refuge is in Stillwater County, Montana, about 31 miles W of Billings, MT (straight-line). GPS: 45.94199, -109.11190.

What are legal shooting hours at Grass Lake NWR?

Migratory game bird shooting hours are generally one-half hour before sunrise to sunset; big game and other seasons follow state rules. See the sunrise/sunset table on this page and confirm in the refuge hunt brochure.

Nearby refuges & public land

Hailstone NWR

Stillwater County, MT · 6.1 mi NW

1 open
🦌🦆🦃🐦🕊️

156 huntable acres

Lake Mason NWR

Musselshell County, MT · 46 mi NE

3 open1 closed
🦌🦆🦃🐦🕊️

8.8K huntable acres

War Horse NWR

Petroleum County, MT · 72 mi NE

3 open
🦌🦆🦃🐦🕊️🎣

2.9K huntable acres

Charles M. Russell WMD

Fergus County, MT · 78 mi N

1 open1 special
🦌🦆🦃🐦🕊️🐇🎣

6.6K huntable acres

Bozeman FTC

Gallatin County, MT · 91 mi W

1 closed
No hunting listed

UL Bend NWR

Phillips County, MT · 127 mi NE

1 special
🦌🦆🦃🐦🕊️🐇🎣

55.8K huntable acres

Waterfowl Production Areas within 35 miles

All refuges in Montana →

Data: USFWS National Hunt Units 2026–2027, Hunting & Fishing Opportunities, Realty Boundaries & Tracts. Page updated October 28, 2026.