Direct Answer
The best septic system installation & replacement contractors in Missoula are verified through Montana Department of Labor (dli.mt.gov). Look for companies with 4.5+ Google stars, 50+ reviews, active MT license, and at least 5 years serving the Missoula area.
Full Explanation
Verify any Missoula contractor at Montana Department of Labor (dli.mt.gov). Request proof of general liability insurance and workers' compensation. Ask for references from recent Missoula projects — local experience matters for understanding permit requirements and area-specific challenges.
Local Factors in Missoula
📍Verify license: Montana Department of Labor (dli.mt.gov)
📍Missoula city permit office issues local permits
📍Check BBB Greater Missoula chapter
📍Require MT state license + local city license if applicable