Mechanics liens

Montana mechanics lien law and deadlines

Montana requires most subs and suppliers on residential work to send a notice of right to claim a lien within 20 days of first furnishing, then file the lien within 90 days of final furnishing.

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Montana's construction lien law (MCA Title 71, Chapter 3, Part 5) turns on one early document: the notice of right to claim a lien. If you are a sub or supplier on a residential job of four units or less, send it to the contracting owner within 20 days after you first furnish services or materials. Then file the lien with the county clerk and recorder within 90 days after your final furnishing, and sue within 2 years. Commercial jobs and original contractors skip the notice, which makes Montana friendlier to commercial trades than to residential ones.

Montana construction lien deadlines at a glance
StepDeadlineStatute
Notice of right to claim a lien to the contracting ownerWithin 20 days after first furnishing (45 days on lender-funded jobs that are not owner-occupied residences)MCA 71-3-531
File a copy of that notice with the county clerk and recorderWithin 5 business days after giving it to the owner; lapses after 1 year unless continuedMCA 71-3-531(6)
File the lienWithin 90 days after final furnishing, or 90 days after the owner files a notice of completionMCA 71-3-535
Serve the owner of recordCertify service with the lien filing (personal service or certified mail, return receipt)MCA 71-3-534
Enforcement suitWithin 2 years after the lien is filedMCA 71-3-562
Release the notice after paymentWithin 5 business days of the owner's requestMCA 71-3-538

Who can claim a Montana construction lien

Anyone who furnishes services or materials under a real estate improvement contract can claim a lien for its contract price (71-3-523). The definition in 71-3-522 is wide. It covers excavation and grading, construction and installation, demolition, repair and remodeling, landscaping, surface or subsurface testing and boring, and preparation of plans, surveys, and architectural or engineering drawings. Design work counts even if the project is never built; in that case the lien attaches when it is filed rather than at the start of work (71-3-535(6)).

Contracts for mining, timber removal, or crop farming are excluded. Contract price includes change orders and extras, and if no price was agreed, the reasonable value of the work.

The notice of right to claim a lien

Montana's preliminary notice has a fixed format set out in 71-3-532, including a capitalized warning that begins "WARNING: READ THIS NOTICE" and states "THIS IS NOT A LIEN." It must be sent by certified mail (effective on mailing) or hand delivered with a written acknowledgment from the owner. A copy then goes to the county clerk and recorder within five business days.

These claimants do not need to send it:

  • Original contractors who furnish directly to the owner at the owner's request.
  • Wage earners performing personal labor.
  • Anyone working on a dwelling for five or more families.
  • Anyone working on an improvement that is partly or wholly commercial.

Late notice is not fatal, but it shrinks the lien. If you send it on day 35, the lien covers only what you furnished in the 20 days before the notice. Say a siding sub starts a custom home on May 1 and sends notice on June 15. Everything delivered before about May 26 is outside the lien. When a regulated lender funds the job and the property is not an owner-occupied residence, the window is 45 days instead of 20.

Filing the lien and enforcing it

The lien is filed with the county clerk and recorder in the county where the property sits, and electronic filing is allowed where the county offers it. It must list the claimant, property, contracting owner, the party you contracted with, the work, the unpaid amount, first and last furnishing dates, and a statement that the notice of right to claim a lien was given or why it was not required. The clerk will not accept it without your certification that a copy was served on each owner of record.

Owners can shorten the timeline by filing a notice of completion. Completion means written acceptance or 30 days with no work, and the owner must publish the notice once a week for three weeks and give a copy to anyone who sent a notice of right to claim a lien. Once it is filed, you have 90 days from that filing. Suit must be brought within two years after the lien is filed.

Lien waivers and releases

Part 5 of the construction lien law does not prescribe a statutory lien waiver form, so waiver language comes from the contract or the lender. What the statute does require is cleanup: once paid, a claimant must file a release of its notice of right to claim a lien, within five business days if the owner asks, with the recorder's file number and filing date.

Public projects and payment bonds

Public contracts in Montana are covered by bond, not by lien. MCA 18-2-201 requires a surety bond from contractors on state and local public work that secures performance and payment of laborers, suppliers, and subcontractors. The public body may accept cash or certain bank instruments instead, and may waive the requirement on projects costing less than $150,000 (or less than $7,500 for school districts). On a waived job, ask what payment security exists before you start. See payment bond for how a bond claim works.

Keeping Montana notices on time

The 20-day clock starts at first delivery, often before the first invoice. Build the notice into job setup on every residential job under five units. Smart Business Automator links job setup, invoicing, and waiver tracking in construction accounts receivable automation. Related state pages: Montana prompt payment rules and Montana contractor license requirements.

Frequently asked questions

When is the Montana notice of right to claim a lien due?

Within 20 days after you first furnish services or materials, or 45 days on certain lender-funded projects that are not owner-occupied residences. A late notice limits the lien to work furnished in the 20 (or 45) days before the notice.

Do commercial projects need a notice of right to claim a lien in Montana?

No. Work on partly or wholly commercial improvements and on dwellings for five or more families is exempt, as are original contractors and wage earners.

How long do I have to file a construction lien in Montana?

Within 90 days after your final furnishing of services or materials, or within 90 days after the owner files a notice of completion.

How long does a Montana construction lien last?

An action to enforce it must be commenced within 2 years after the lien is filed.

Can architects and engineers file a lien in Montana?

Yes. Preparing plans, surveys, and architectural or engineering drawings is part of a real estate improvement contract, even if the project is not built.

Sources

  1. Montana Code Annotated 2025: Title 71, Chapter 3, Part 5 index
  2. MCA 71-3-522: Definitions
  3. MCA 71-3-531: Notice of right to claim lien required
  4. MCA 71-3-532: Content of notice of right to claim lien
  5. MCA 71-3-533: Notice of completion
  6. MCA 71-3-534: Filing with county clerk
  7. MCA 71-3-535: Attachment of lien, filing
  8. MCA 71-3-538: Release of notice of right to claim lien
  9. MCA 71-3-562: Limitation on actions
  10. MCA 18-2-201: Security requirements for public contracts

Laws and rates change. Confirm current requirements with the state agency before you bid, file, or pay. This page is general information, not legal advice.

Written and edited by

Maurice Francois writes and edits construction operations guides for Smart Business Automator. More from Maurice on the Scaling Legends podcast.

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