To buy a tax lien in Montana you bid on a certificate, not on the property. The county certificate sale is run by the County Treasurer. You are buying the delinquent debt, the statutory interest it earns, and the right to force a sale if the owner never repays.
Each step below is drawn from Montana statute, not general advice. The exact sale dates, platform, and deposit amounts are set county by county, so confirm the specifics on your county page before you register.
New here? Most beginners start with a certificate (the lien path). The deed steps below apply once you hold a certificate long enough to force a sale, or you bid directly at a tax deed auction. Not sure which is for you? Start with tax lien vs tax deed.
Learn the timeline and lien priority
Montana property taxes are billed in halves. The first half is payable by 5 p.m. on November 30, or within 30 days after the tax notice is postmarked if that is later, and the second half by 5 p.m. on May 31. An unpaid half is delinquent from that moment, draws interest at 5/6 of 1 percent a month until paid, and has a one time 2 percent penalty added to it. Taxpayers on the alternative payment schedule for primary residences pay one seventh each month from November 30 through May 31 and fall under the same interest and penalty if a payment is missed. A taxpayer may pay the current year without clearing an older delinquency, and paying the current year is not a redemption of any earlier tax lien. Parcels still delinquent at the end of that cycle get a county tax lien attached no later than the first working day in August. Understand this before you commit any money.
Find the advertised delinquent list
Before the certificate sale, the County Treasurer advertises the delinquent parcels. There is no sale date to attend. The statewide calendar is fixed by statute rather than published per county. The treasurer publishes or posts the notice of pending attachment on or before the last Monday in June, mails the assessed owner a notice at least 2 weeks before attaching, and attaches the tax lien no later than the first working day in August. An investor who wants an assignment must mail the assessed owner the statutory notice of pending assignment by certified mail at least 2 weeks before paying, and that notice may not be sent earlier than August 15 or more than 60 days before the purchase, so the earliest practical assignment date in any county is about August 29. Assignments of unclaimed liens remain available from the treasurer year round after that. Pull that list for your target county and shortlist the parcels worth researching.
Register, then buy at the amount due
Register with the state and the county ahead of the sale, and be ready to pay the full amount due rather than a deposit. There is no auction in the ordinary sense. A certificate sells for the amount due on it and every one of them earns the statutory 10 percent, so the sale allocates access rather than price. Ask the county who holds priority ahead of you and what you must file, and by when, to be eligible at all. There is no statutory minimum return, so what you earn is decided at the sale. Nothing is bid in Montana because nothing is auctioned. Montana repealed its tax lien sale. Title 15, chapter 17, part 2 is captioned "Tax Lien Sale (Renumbered and Repealed)" in the official code, 15-17-201 through 15-17-214 are shown as repealed, and the one surviving section, old 15-17-212, was renumbered 15-17-125 and now describes an ATTACHMENT rather than a sale. Under 15-17-125(1)(a) the treasurer attaches the lien and the county is the possessor of it unless it is assigned under 15-17-323. Under 15-17-323(1)(a) the treasurer must assign that lien to any person who first mails the assessed owner a notice of pending assignment and then pays the delinquent taxes, penalties, interest and costs. The amount is fixed by the payoff and the rate is fixed by 15-16-102, so neither price nor yield is competed. What a county allocates is access: 15-17-323(1)(b) directs each treasurer to write a policy for the case where more than one person seeks the same assignment, developed with the county clerk and recorder and the county attorney, and those policies differ. Madison County serves the counter first come, first served and breaks a tie by drawing numbers from a cup. Yellowstone County takes one ranked parcel list per investor by noon on the day before assignment day and runs a randomized snake draft at 10:00 a.m., then sells whatever is left first come, first served. Gallatin County takes ranked lists by noon on August 30 and runs a lottery on September 1. Those dates and fees come from each county's own published timeline and move with the year, so read them as the three shapes a policy takes rather than as fixed dates. TWO STATUTORY STEPS LOOK LIKE A SALE HERE AND ARE NOT AN INVESTOR AUCTION. The first is the attachment itself on the first working day in August, which several county offices still call the tax lien sale and advertise in the newspaper each summer; it transfers nothing to an investor, it moves the lien to the COUNTY, and the published notice under 15-17-122 is a warning to delinquent owners rather than a bidder notice. The second is the county tax-deed land auction under 7-8-2301, a genuine public auction but of land the county already owns after taking its own tax deed, ordered by the county commissioners within 6 months of acquiring title at a price the board fixes in advance. Neither one is a tax lien auction, and Montana holds no tax lien auction of any kind. A Montana sheriff's sale or foreclosure sale notice is a mortgage foreclosure and has nothing to do with the tax lien process.
Collect interest or wait out redemption
Interest runs at 5/6 of 1 percent a month, which is 10 percent a year, on the whole amount the assignee paid. Mont. Code Ann. 15-18-114(2)(a) is explicit: on redemption the treasurer pays the assignee the amount the assignee paid the county for the property tax lien, plus any subsequent taxes the assignee paid under 15-18-112, plus interest at the 15-16-102 rate from the date of each payment to the date of redemption. Because 15-17-323(1)(a) fixes the assignment price at the payoff, there is no premium to dilute the base. The 2 percent delinquency penalty is a one time charge already built into the payoff the assignee buys, not an extra return on top. The county's assignment fee is a cost under 15-17-121(3)(a)(iii) and rides on the lien. Montana sets no minimum return, so a lien redeemed a month after assignment earns about a month of interest and nothing more. Subsequent-year taxes may be added to an existing assignment only between June 1 and July 31, or after the date in 15-16-102(4)(b) and before July 31 for a parcel in the property tax assistance program, and they earn the same rate from the date paid. The clock runs from attachment of the tax lien, which happens no later than the first working day in August, and it ends on the first working day in August of the third year after that. Redemption stays open for the whole period and the assignee cannot shorten it. On the residential auction track the right to redeem runs further still: the statutory notice tells the parties that a tax deed will be auctioned unless the lien is redeemed before the date of the auction, and 15-18-112(4) lets a particular tax year be redeemed until a deed has issued under 15-18-211 or 15-18-220. Interest and costs keep accruing until the day of redemption, and the county treasurer, not the assignee, calculates the payoff as of the date of payment. A redemption before the lien is assigned goes to the county; after assignment the treasurer pays the assignee. To redeem, the owner pays The full amount of the property tax lien, which is the delinquent taxes plus the 2 percent penalty, the interest accrued at 5/6 of 1 percent a month and the county's costs, plus every subsequent tax the assignee paid with interest and penalty at the same 15-16-102 rate. The treasurer then pays the assignee the amount the assignee paid for the lien, plus any subsequent amounts paid, plus interest at the 15-16-102 rate from the date of each payment to the date of redemption, and sends it to the address on the assignment certificate within 30 days. Anything left over is credited to the taxing funds the taxes would originally have gone to. Costs are the category to check before assuming a payoff: they include the county's charge for assigning the lien, the certified mailings, a title search to the extent needed to identify interested parties, publication and the filing of proof of notice, and the treasurer may require receipts or accept a notarized affidavit of costs. If they redeem, that payoff is your return; if they never do, the certificate becomes your path to the property.
Apply for a tax deed
Montana runs no scheduled county tax deed auction and no calendar of deed sales. Two different endings apply once the redemption period runs out, and which one applies is a property of the parcel. For ordinary property the treasurer simply grants the assignee a tax deed under 15-18-211 for a 25 dollar deed fee plus the county's actual notice costs, with no auction and no bidders. For property that contains a dwelling currently occupied by the legal titleholder of record, and that is classified residential under 15-6-134, agricultural under 15-6-133(1)(a) or (1)(c), or forest under 15-6-143, the assignee may not take the deed directly. Under 15-18-219 the assignee files an application with the treasurer and pays a 25 dollar application fee, the redemption amount on any unassigned liens or liens held by other assignees, any delinquent taxes, penalties and interest, and the current taxes. The treasurer then holds a public auction in the county within 60 days of receiving that application, under 15-18-220. That auction exists so the owner's equity is paid out rather than forfeited, which is why the opening bid carries half the assessed value. If no assignment was ever taken, no deed issues to the county unless the county commissioners direct the treasurer by resolution. The treasurer publishes notice of the auction with the date, time, location, legal description, deposit requirement and minimum opening bid, and may not accept a bid below the opening bid. The opening bid is the sum of the amount required to redeem the tax lien, which is the delinquent taxes, penalties, interest and costs, plus everything the assignee paid on application under 15-18-219(2), plus the 25 dollar tax deed fee and recording fees, plus an amount equal to half of the most recent assessed value of the land and of the dwelling. An independent appraisal conducted within 6 months of the auction and meeting Montana Board of Real Estate Appraisers standards may be used in place of the assessed value, in which case half the appraised value of the land and dwelling sets that component. The auction is held during the treasurer's regular office hours in the county where the property is located, and it may be conducted electronically. A foreign entity may not buy at this auction and an entity must show written proof of domestic entity status before the treasurer will accept its opening bid.
Bid at the tax deed auction
The County Treasurer sells the property at public auction to the highest bidder. The high bidder posts a nonrefundable deposit with the county treasurer at the time of sale of 5 percent of the bid or 200 dollars, whichever is greater, and the deposit is applied to the sale price on full payment. Notice of the deposit requirement must be posted at the auction site, and the treasurer may require bidders to show they can post it. The treasurer may refuse to recognize a bid from someone who previously bid and then refused to honor the bid. Full payment of the purchase price plus the treasurer's auction costs is due within 24 hours of the sale, excluding weekends and legal holidays. If a high bidder who is not the assignee fails to pay, the treasurer cancels that bid and offers the deed to the next highest bidder for the amount bid, repeating down the list until someone pays or no bidders remain. If the assignee is the high bidder, the assignee pays auction costs plus any part of the opening bid not already paid, including filing fees, the tax deed fee and half the most recent assessed value of the land and dwelling, and a failure to pay within the same 24 hours cancels the assignment entirely. If no one bids at all, or nobody pays, the treasurer cancels the assignment and files a notice of cancellation with the county clerk and recorder. The investor loses the lien in that case, so an assignee on this track should treat the auction as a real risk to the position, not a formality.
Or buy over the counter
You do not have to wait for an auction. Every Montana tax lien is over the counter, because that is the only way one is ever acquired. The county holds the lien from the moment it attaches, and 15-17-323(1)(a) requires the treasurer to assign it to any person who first mails the assessed owner a notice of pending assignment by certified mail and then pays the delinquent taxes, penalties, interest and costs. The notice must be mailed at least 2 weeks before the payment, not earlier than August 15 and not more than 60 days before the purchase, and the buyer must hand the treasurer proof of the mailing. Counties add their own assignment fee, which ran from 50 to 75 dollars per parcel at the offices checked for this record. The treasurer issues an assignment certificate in the statutory form, mails a copy to the assessed owner, and files a copy with the clerk and recorder. In the first days after attachment most counties run an allocation step because several investors want the same parcels, and after that step the remaining liens sit with the treasurer and can be assigned on demand for the rest of the year. An assignee may pass the lien on to a new assignee for any consideration, which is binding only once a signed statement naming the old and new assignees and describing the property is filed with the treasurer. Montana keeps no lands available list and no struck to the state inventory. Parcels are never struck to the state, because the lien sits with the COUNTY from the day it attaches. What does exist is county tax-deed land. Where the county itself ends up with a tax deed, the board of county commissioners must within 6 months enter an order to sell the land at public auction, donate it to a municipality, donate it or sell it at a reduced price to a qualifying corporation for low income housing, or retain it. A sale may not go below a price the board fixes in advance, which may be set high enough to recover the taxes, assessments, penalties and interest due when the deed was taken plus the county's costs of taking the deed and running the sale. The county clerk publishes the notice with the list of lands, the department of revenue fair market value and the time and place. If no bids come in, the board orders another auction within 6 months and may reset the price, and after a second failure the land can be managed or disposed of under Title 7, chapter 8, part 25. Before bidding, note that the delinquent taxpayer or a successor may repurchase the land from the county up to 24 hours before the time fixed for the first offering.
One more step: clear the title
Winning a tax deed does not hand you marketable title. Before you can resell to a normal buyer or insure the parcel, you will usually need a quiet title action, which takes months and costs money. Fold that cost into your maximum bid and read what you actually own after a tax deed before you bid. A tax deed also does not wipe out everything: select governmental and municipal liens can survive, and a federal tax lien carries a 120-day IRS redemption right, so check what survives a tax deed too.
Buying tax liens in Montana: common questions
How do you buy a tax lien in Montana?
Can you buy Montana tax liens online?
More Montana answers, including redemption and statute detail, are on the Montana tax sale FAQ.
New to this? Start with tax lien vs tax deed and the full Montana walkthrough, then value a parcel with the due diligence guide.
Steps verified Sep 10, 2026 against Montana statutes.
Tax Sale Atlas publishes educational information about public tax sale processes. This is not legal, financial, or investment advice. Rules, dates, and fees change; confirm with the county office before you bid.