About this tournament

Mack Days is both a tournament and a conservation program. The Confederated Salish and Kootenai Tribes run it twice a year — Spring (March–May) and Fall (September–November) — to suppress non-native lake trout (“macks”) on Flathead Lake, opening up habitat for native bull trout and westslope cutthroat. The Fall 2026 event runs Thursday September 10 through Sunday November 8, a full nine weeks of open-fishing days that any angler with a valid license and a Flathead Lake AIS-inspected boat can join.

The format is unique. There’s no single weigh-in or one-day winner — anglers turn in lake trout at Blue Bay (event headquarters near Polson) or weekend satellite stations and accumulate entries across the entire nine-week window. Mondays through Thursdays fish for tagged-fish bounties and bonus totals; Fridays through Sundays add lottery drawings, special category prizes, and top-angler standings. Payouts scale with how many fish you enter — examples from the most recent event paid roughly $45 for 11–30 fish, $870 for 276–300, $1,850 for 476–500, and nearly $6,000 for 1,150+ entries. CSKT releases the full bonus chart each year before the event.

The tagged-fish pool is what draws casual anglers — a single lake trout can be worth up to $10,000. The 2025 Fall event released one $10,000 tag, three $5,000 tags, five $1,000 tags, and over 9,000 smaller bounties from $100 to $500, all identifiable by a clipped adipose fin. Combined with thirty separate lottery drawings worth $500–$2,000 and top-angler category prizes (overall, women, youth, 70+), the prize structure rewards both hardcore tournament regulars and one-fish-lucky weekend anglers.

Entry is free, but participants must register through mackdays.com, pay the standard CSKT/Flathead Lake fishing-license fees, and pass mandatory AIS inspection. CSKT keeps the Blue Bay Campground open to Mack Days anglers only for the duration of the event. Trolling is the dominant tactic in fall — anglers run downriggers over deep main-lake basins — and shore fishing along Polson Bay tends to fish better in fall than spring.

Schedule

• Thu Sep 10, 2026 — Fall Mack Days opens; daily lake trout entries begin at Blue Bay
• Mon–Thu weekly — Fish for tagged-fish bounties + bonus totals; Blue Bay weigh-in 10 a.m. to 30 min before sunset
• Fri–Sun weekly — Fish for lottery drawings, tagged fish, bonuses, and category prizes; weekend satellite weigh-ins at Somers (5:00–6:00 p.m.), Big Arm (6:00–6:30 p.m.), Wayfarers (6:30–7:00 p.m.), and Salish Point (7:00–7:15 p.m.)
• Sun Nov 8, 2026 — Final fishing day; final lottery drawings and category-prize awards

Entry & Prizes

Entry: No entry fee for the tournament itself — anglers register at mackdays.com. A valid Flathead Lake fishing license (issued through CSKT) is required. Boats must pass AIS inspection.

Prizes: Cash payouts scale with total lake trout entered (example tiers: 11–30 fish = $45, 276–300 = $870, 476–500 = $1,850, 1,150+ = ~$5,957). Tagged-fish bounties include one $10,000, three $5,000, five $1,000, and over 9,000 smaller tags worth $100–$500. Thirty lottery drawings worth $500–$2,000 each. Separate top-angler awards by overall, ladies, youth, and 70+ categories ($200–$950).

What to expect

Fall fishes differently than spring — trolling becomes the dominant tactic, with downriggers run over deep main-lake basins (think 80–200 ft) along the western and northern shores. Jigging holds up well, especially over offshore humps. Shore anglers actually do better in fall than spring, particularly around Polson Bay. Plan to weigh in often — payouts scale with total entries, so the more frequently you turn in fish, the more bonus brackets you accumulate. Always check the adipose fin: a clipped one means tag money.

History

Mack Days has been run twice a year on Flathead Lake for two decades as a CSKT-led suppression program for non-native lake trout. In April 2026 anglers landed the program’s 50,000th lake trout entry — a milestone that underscores both the scale of the harvest and the role anglers play in protecting Flathead’s native bull trout and westslope cutthroat fisheries.

Contact