Investing guides / Montana

Montana tax sale investing: buy the tax debt, earn the rate

How it works in Montana

In Montana you are not buying property at the sale — you are buying the county's tax lien certificate for the amount of taxes owed, and the owner owes you interest until they redeem.

Interest / penalty: 10% per year (5/6 of 1% per month) plus a 2% penalty on the delinquent amount (MCA 15-16-102)

Redemption: 3 years from attachment of the tax lien, ending the first working day in August (MCA 15-18-111(1)); 2 years for property subdivided as a residential or commercial lot with delinquent special improvement district / rural SID assessments and no habitable dwelling or commercial structure on it (MCA 15-18-111(2))

When sales happen: No conventional auction in most counties: the county attaches the lien no later than the first working day in August (notice by the last Monday in June) and holds it; investors acquire it thereafter by assignment from the county treasurer (MCA 15-17-323)

Where sales run: Mostly in-person / direct assignment through the county treasurer, No statewide online auction platform for the lien assignment

Governing law: Montana Code Annotated Title 15, Chapters 16-18 (MCA 15-16-102; 15-17-121 et seq., 15-17-323; 15-18-111; 15-18-211, 15-18-219 to 15-18-221)

The investor's edge

Your edge is rate discipline: know the statutory maximum, know what the sale historically bids down to in your target counties, and set a floor rate you will not cross before the sale starts.

Montana is assignment-based, not bid-based: there is generally no bidder registration, deposit or rate bidding, and the assignee must first mail the statutory notice of pending assignment (MCA 15-17-323) and pay taxes, penalty, interest, costs and the county assignment fee. CORRECTION to common summaries: the 2-year period is not a general 'abandoned property' rule — it is the vacant subdivided-lot / delinquent SID-assessment rule in 15-18-111(2). For residential property, the deed stage is a statutory public auction: after the redemption period expires the assignee applies for a tax deed under MCA 15-18-219 (paying other liens, delinquent and current taxes, plus a $25 fee, with notice to interested parties), and the county treasurer must hold a public auction in the county within 60 days of the application (MCA 15-18-220, as amended by SB 306, 2025). The opening bid equals the redemption amount + the assignee's 15-18-219 payments + deed/recording fees + one-half of the most recent assessed (or appraised) value of the land and dwelling; payment is due within 24 hours, and if the auction fails the assignment is cancelled. Proceeds are distributed under MCA 15-18-221 (assignee repaid its amounts; surplus to the legal titleholder of record). Non-residential property still follows the direct-deed route of MCA 15-18-211.

Full legal reference: Montana tax sale laws. Verified 2026-10-30 against the sources on that page. Educational only, not investment advice.