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Tax Sale Atlas

Petroleum County, MT tax sales

Tax Sale Atlas maps the Petroleum County, MT tax sale, one of 2,862 counties in 36 states. Montana sells tax lien certificates paying up to 10%. Sale office, calendar and list locations read from state rules plus what the county publishes on Sep 11, 2026.

How tax lien and tax deed sales work in Petroleum County, seat of Winnett: sale calendar, auction platform, over-the-counter lists, and the offices that run each sale.

New to tax sales? Read how Montana tax sales work or look terms up in the glossary.

Next sale
Nothing is scheduled in advance.
Format
In person
County office
(406) 429-5107
Every displayed fact carries a source badge. Verified Sep 11, 2026 against official county and state pages.How we verify
On this page
Look up a sale detail

County Treasurer. In person at the county treasurer's office during regular office hours. Mont. Code Ann. 15-18-220(6) permits a county to conduct the auction electronically but does not require it, and there is no statewide platform.. As applied for. There is no deed sale calendar, and most parcels never reach an auction at all.

Record quality: medium. Last verified: 2026-09-11.

Mont. Code Ann. 15-18-220 - Sale at public auction, notice of auction, cancellation of assignment for unsuccessful auction, foreign entity prohibition (source accessed 2026-09-10)

Recorded reference information. Verify current sale conditions with the county. Read the full sale details.

Link to this detail

How Petroleum County sells delinquent taxes

Tax certificate sale (lien)

In person at the county treasurer's counter, or by mail or email where the county allows it. Montana holds no tax lien auction, so there is no online bidding platform, no registration portal and no vendor to sign up with.
Run by
Petroleum County Treasurer
Frequency
annual
Registration
No bidder registration, no deposit and no auction account, because nothing is bid.
When it runs
There is no annual tax lien auction in Montana, so the calendar is statutory rather than a sale date. The Treasurer publishes or posts the notice of pending attachment of a tax lien "on or before the last Monday in June," the lien attaches to the county in early August, and an investor's notice of pending assignment may be mailed "not earlier than August 15" and must be mailed "at least 2 weeks prior to the date of the payment." The earliest an assignment can close is therefore about August 29, and the Treasurer takes assignment requests year round after that.
Registration and deposit

No bidder registration, no deposit and no auction account, because nothing is bid. To take an assignment, mail the statutory Notice of Pending Assignment by certified mail to the person the property was assessed to, wait the required two weeks, then bring proof of that mailing to the Treasurer at 302 East Main in Winnett and pay the delinquent taxes plus penalties, interest and costs in full. The Treasurer then issues an assignment certificate in the form set by Mont. Code Ann. 15-17-323. Montana requires each treasurer to adopt a written policy for ranking competing requests on the same parcel, and Petroleum County does not post its fee or its policy, so call (406) 429-5107 first to confirm the assignment fee, the accepted payment method and how a contested parcel is allocated.

Sale format and venue
Petroleum County is Montana's least populous county, and the Treasurer handles lien assignments over the counter alongside property tax and motor vehicle work. The county itself holds every tax lien that attaches, and an investor buys by assignment rather than by bidding, so the return is the statutory rate and there is no premium or rate bid-down. Real property taxes run delinquent after November 30 and May 31 and draw a 2 percent penalty plus 10 percent annual interest, which is what feeds the following summer's lien attachment. One narrow situation does produce an auction: where the parcel holds a dwelling occupied by the legal titleholder, the assignee cannot take a deed directly and the Treasurer must hold a public auction on that single parcel within 60 days of the application. No such parcel notices appear on the Petroleum County website, so ask the Treasurer directly whether any are pending.
Source: Mont. Code Ann. 15-17-323 - Assignment of rights, form· Verified Sep 11, 2026

Tax deed sale

In person at the county treasurer's office during regular office hours. Mont. Code Ann. 15-18-220(6) permits a county to conduct the auction electronically but does not require it, and there is no statewide platform.
Run by
County Treasurer
Frequency
As applied for. There is no deed sale calendar, and most parcels never reach an auction at all.
Typical timing
Nothing is scheduled in advance.
When it runs
Nothing is scheduled in advance. Once the redemption period runs out, 3 years after attachment or 2 years for an unimproved subdivided lot with delinquent improvement district assessments, the path forks on what is standing on the parcel. Ordinary property is deeded straight to the assignee under Mont. Code Ann. 15-18-211 for a 25 dollar deed fee plus the county's notice costs, with no auction and no bidders. Property with a dwelling currently occupied by the legal titleholder of record goes to a public auction instead: the assignee files a tax deed application with the treasurer after the redemption period expires, and the treasurer must hold the auction in the county within 60 days of receiving it. The treasurer publishes the auction notice with the date, time, location, legal description, deposit requirement and minimum opening bid. The auction runs during the treasurer's regular office hours and may be conducted electronically.
Registration and deposit

Bidders at a Montana tax deed auction do not pre-register, but three requirements bind at the auction itself. An entity must give the treasurer written proof that it is a domestic entity before the treasurer will accept its opening bid, and a foreign entity may not buy at all. The high bidder posts a nonrefundable deposit at the time of sale of 5 percent of the bid or 200 dollars, whichever is greater, applied to the price on full payment, and the treasurer may ask bidders to show they can post it. 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, and a bidder who misses it loses the parcel to the next highest bidder. Confirm the accepted payment methods with the county treasurer before the auction opens.

Sale format and venue
The opening bid is the amount needed to redeem the lien, plus everything the assignee paid on application, plus the tax deed and recording fees, plus an amount equal to half the most recent assessed value of the land and of the dwelling. An independent appraisal meeting Montana Board of Real Estate Appraisers standards and conducted within 6 months may stand in for the assessed value. The treasurer may not take a bid below that figure. The half-value component, and anything bid above the opening bid, is surplus: the treasurer repays the assignee first where someone else buys, then pays the surplus to the legal titleholder of record within 30 days. If nobody bids, or no bidder pays, or the assignee wins and fails to pay inside the 24 hours, the treasurer cancels the assignment and files a notice of cancellation, and the investor loses the lien position entirely. The owner may redeem right up to the day of the auction.
Source: Mont. Code Ann. 15-18-220 - Sale at public auction, notice of auction, cancellation of assignment for unsuccessful auction, foreign entity prohibitionMont. Code Ann. 15-18-220· Verified Sep 10, 2026

Petroleum County tax sale list and auction calendar

For Petroleum County tax sale 2026 searches, use the county-run sources below rather than a copied parcel list, and confirm the parcel, registration cutoff, deposit, and payment deadline against the county before you bid. If the parcels on this list are vacant land rather than houses, what buying land at a tax sale hands you is the place to start.

  1. Get the advertised list

    A county sale-list URL is still being verified. Use the office and platform details on this page before relying on a copied list.

  2. Register to bid

    Ask the county office how and when to register; many counties close registration days or weeks before the sale.

  3. Sale day

    Nothing is scheduled in advance. The sale is live and in person; there is no online bidding platform. Confirm the venue and hour with the county office before you go.

  4. Confirm with the office

    If the list, platform, and notice disagree, use County Treasurer as the source to confirm which parcels are actually offered.

Before you bid in Petroleum County

  1. Start with the live sale list

    The county sale-list URL is still being verified. Use the county office contacts below and confirm the advertised parcels directly before you price a bid.

  2. Confirm registration and deposit

    Bidders at a Montana tax deed auction do not pre-register, but three requirements bind at the auction itself. An entity must give the treasurer written proof that it is a domestic entity before the treasurer will accept its opening bid, and a foreign entity may not buy at all. The high bidder posts a nonrefundable deposit at the time of sale of 5 percent of the bid or 200 dollars, whichever is greater, applied to the price on full payment, and the treasurer may ask bidders to show they can post it. 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, and a bidder who misses it loses the parcel to the next highest bidder. Confirm the accepted payment methods with the county treasurer before the auction opens.

  3. Check the state rules that change the bid

    Read the Montana due-diligence checklist before bidding. Redemption, liens that survive a tax deed, title cleanup, and payment deadlines can change what a parcel is worth. Which liens survive is state law, so read what survives a tax deed in Montana before you price the title work.

  4. Set a walk-away number

    Work out what the parcel is actually worth with the rural land value estimator, then turn it into a ceiling with the tax deed max-bid calculator.

Over-the-counter (leftover) purchases

Every Montana tax lien is effectively over the counter, because assignment is the only way one is ever acquired. The county holds each lien from the day it attaches, and the treasurer must assign it to any person who mails the assessed owner the statutory notice and pays the delinquent taxes, penalties, interest and costs plus the county's assignment fee. After the late August allocation step, whatever is left sits with the treasurer and can be assigned on demand for the rest of the year, subject to the same notice rules: not earlier than August 15, mailed at least 2 weeks before payment and no more than 60 days before it. Older tax years are assignable the same way. Separately, land the county itself took by tax deed is sold at a public auction the county commissioners must order within 6 months of acquiring title, at a price the board fixes in advance, with the list of lands and the time and place published by the county clerk. That county land auction is not a tax lien or tax deed sale and the delinquent taxpayer may repurchase up to 24 hours before the first offering.

New to this path? Read how over-the-counter certificates work. Every state has its own name for what goes unsold, so check what Montana calls its leftover tax-sale inventory.

Use the arrow keys to switch between these sections.

County offices

Tax Collector (runs the certificate sale)

Petroleum County Treasurer

(406) 429-5107

302 East Main, PO Box 226, Winnett, MT 59087-0226

Official website

County notes

  • Petroleum County publishes no online delinquent-tax list and no assignment list. Montana instead requires the Treasurer to keep a list of every delinquent property on file in the office, open to inspection, and to publish or post only the notice of pending attachment. Get the working list by calling the Treasurer at (406) 429-5107 or visiting the office at 302 East Main in Winnett.
  • Watch for the late-June notice of pending attachment in the county's legal notices. Montana counties publish it in a qualifying local newspaper, and where no newspaper in the county qualifies, the commissioners designate three public posting places instead, one of which may be the county website. In a county this small, the courthouse posting is worth checking in person.
  • The Treasurer's office line is (406) 429-5107. The county contact directory also lists a direct line for the Treasurer at (406) 429-5551, useful when the main line is tied up at the motor vehicle counter.
  • Budget for a courthouse visit rather than an online transaction. Petroleum County offers no portal for viewing delinquencies, requesting an assignment or paying, so plan on certified mail for the owner notice and an in-person or mailed payment to the Treasurer.
  • Real property taxes here are due in two installments, November 30 and May 31. A parcel must already be delinquent for the county's lien to attach the following August, so a first-installment miss in December is the earliest signal that a parcel may become available by assignment.

Montana rules

Max interest rate
10% per year, fixed by statute (nothing is bid)
Minimum return
No statutory floor; every certificate earns the same statutory rate
Redemption
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.
Deed deposit
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.
Surplus proceeds
Montana pays the owner's equity out rather than letting it be forfeited. The portion of the opening bid equal to half the most recent assessed value of the land and of the dwelling is treated as surplus funds, and so is anything a winning bid adds above the opening bid. Where the deed is bought by someone other than the assignee, the treasurer first repays the assignee the amount paid for the assignment, including delinquent taxes, penalties, interest and costs, plus everything paid on the tax deed application under 15-18-219(2). The treasurer then distributes the surplus to the legal titleholder of record within 30 days of receiving payment from the purchaser, whether or not the titleholder lives in Montana. On the ordinary non-auction track there is no sale, no bidding and no surplus: the assignee receives the deed itself.
Governing statute
Mont. Code Ann. Title 15, ch. 17

A tax deed does not convey marketable title. Most buyers file a quiet title action before they can resell or insure the property. See the due diligence guide.

See the full Montanarules and every county →

Frequently asked questions

Does Petroleum County, Montana sell tax liens or tax deeds?

Petroleum County follows Montana's tax lien state system.

When is the Petroleum County tax certificate sale?

There is no annual tax lien auction in Montana, so the calendar is statutory rather than a sale date. The Treasurer publishes or posts the notice of pending attachment of a tax lien "on or before the last Monday in June," the lien attaches to the county in early August, and an investor's notice of pending assignment may be mailed "not earlier than August 15" and must be mailed "at least 2 weeks prior to the date of the payment." The earliest an assignment can close is therefore about August 29, and the Treasurer takes assignment requests year round after that. The sale is held in person. Always confirm the exact date with the County Treasurer before the sale.

How often does Petroleum County hold tax deed sales?

Petroleum County holds its tax deed sale As applied for. There is no deed sale calendar, and most parcels never reach an auction at all. Nothing is scheduled in advance. Each sale is scheduled and advertised in advance, so check the county's tax deed calendar for the next posted date.

I own a property in this sale. Can I stop it?

Often yes, by paying the overdue taxes, interest, and costs before the deadline. Montana's redemption rule: 3 years from attachment of the tax lien, ending on the first working day in August; 2 years for a subdivided residential or commercial lot with delinquent improvement district assessments and no habitable dwelling or commercial structure. Call the County Treasurer as early as possible for your exact payoff and options; deadlines are strict. Free help: lawhelp.org lists legal aid programs, and consumerfinance.gov lists HUD-approved housing counselors.

Verified Sep 11, 2026 against official county and state sources.

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.

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Call Petroleum County Treasurer