Construction disputes and payment issues are an unfortunate reality in the real estate industry. Whether you are a contractor who has not been paid for completed work or a property owner facing an unexpected lien claim, understanding Missouri's mechanic's lien law is essential to protecting your interests. Missouri's mechanic's lien statute, found in RSMo Chapter 429, provides a structured framework for securing and enforcing construction-related claims — but the rules are detailed and the deadlines are unforgiving.

What Is a Mechanic's Lien?

A mechanic's lien is a legal claim against real property by someone who has provided labor, materials, or services to improve that property. The lien attaches to the property itself — not to the person who owes the debt — which means the property serves as security for the unpaid claim. If the lien is valid and enforced, the property can be sold at a court-ordered sale to satisfy the debt.

In Missouri, mechanic's liens are available to a broad range of participants in the construction process, including general contractors, subcontractors, laborers, material suppliers, architects, engineers, and surveyors. The statute is designed to ensure that those who improve property are paid for their contributions, even when the chain of contractual relationships makes direct collection difficult.

Who Can File a Mechanic's Lien in Missouri?

Under RSMo Chapter 429, any person who provides work, labor, or materials for the improvement of real property under a contract (written or oral) with the property owner — or with the owner's agent, contractor, or subcontractor — may file a mechanic's lien. This includes:

General contractors who contract directly with the property owner
Subcontractors who contract with the general contractor
Material suppliers who provide lumber, concrete, fixtures, or other materials used in construction
Laborers who perform physical work on the property
Design professionals such as architects, engineers, and surveyors who provide professional services for the improvement

The breadth of this coverage means that even suppliers who never set foot on the property may have lien rights if their materials were incorporated into the improvement.

Filing Deadlines and Requirements

The deadlines for filing a mechanic's lien in Missouri are strict, and missing them extinguishes the right entirely. There are no extensions, no equitable exceptions, and no second chances.

The Six-Month Rule

Under RSMo 429.080, both general contractors and subcontractors must file their lien statement with the circuit court within six months after the indebtedness accrues — that is, within six months of the last date they provided labor or materials to the project. This deadline runs from the date of the last work performed or the last materials delivered — not from the completion of the overall project.

Notice Requirements

General contractors have their own prerequisite: under RSMo 429.012, the original contractor must serve a statutory disclosure notice to the property owner — in 10-point bold type — with the contract or first invoice, before receiving any payment. This notice warns the owner that subcontractors may file liens if they are not paid. Failure to provide this disclosure is fatal to the general contractor's own lien rights.

For subcontractors and material suppliers, there is a separate additional requirement under RSMo 429.100: they must give at least ten days' written notice to the property owner before filing the lien, stating the amount claimed and from whom it is due. This notice must be served within the same six-month window. Both the filing deadline and the notice requirement are strictly enforced — missing either one extinguishes the lien right entirely.

What the Lien Statement Must Include

The lien statement filed with the circuit court must contain specific information, including a description of the work performed or materials furnished, the amount claimed, the name of the property owner, a legal description of the property, and a statement that the work was authorized by the owner or the owner's agent.

Errors in the lien statement — such as an incorrect legal description, an overstated amount, or a missing party name — can jeopardize a lien claim. Missouri courts apply a "reasonable and substantial compliance" standard to lien statement contents, meaning minor technical deficiencies may not be fatal. In Custom Construction Solutions, LLC v. B & P Construction, Inc., 684 S.W.3d 148 (Mo. Ct. App. 2023), the court reaffirmed that a property description need only be sufficient to allow someone familiar with the locality to identify the property. However, while courts may forgive minor imprecisions in lien statements, they remain strict about substantive requirements — particularly the statutory deadlines for filing and enforcement.

Where to File

The lien statement must be filed with the clerk of the circuit court in the county where the property is located. If the property spans multiple counties, the lien should be filed in each county.

Enforcing a Mechanic's Lien

Filing the lien statement is only the first step. Under RSMo 429.170, the claimant must file a lawsuit to enforce the lien within six months after filing the lien statement. If no suit is commenced within this period, the lien expires and cannot be revived. This creates a two-stage deadline system: six months to file the lien (RSMo 429.080), then six months to file the enforcement action (RSMo 429.170).

The enforcement lawsuit asks the court to order the sale of the property to satisfy the lien. In practice, most construction disputes involving mechanic's liens are resolved through negotiation or settlement before reaching this stage — the existence of the lien creates significant leverage because it clouds the property's title and can prevent the owner from selling or refinancing.

If the case does proceed to trial, the court evaluates whether the work was performed, whether it was authorized, whether the lien was properly filed within the statutory deadlines, and the amount owed. If the court finds the lien valid, it can order the property sold at a judicial sale, with the proceeds distributed to satisfy the lien.

Protecting Your Property from Mechanic's Liens

If you are a property owner undertaking a construction project, there are several steps you can take to protect yourself from mechanic's lien claims:

Use written contracts. A detailed written contract that specifies the scope of work, payment schedule, and lien waiver requirements gives you a clear record of what was agreed upon.

Require lien waivers. Before making progress payments to your general contractor, require the contractor to provide lien waivers from all subcontractors and suppliers who have been paid. This creates a paper trail confirming that downstream parties have been compensated.

Verify payments are flowing. If you are paying the general contractor but subcontractors are not being paid, you may face lien claims from those subcontractors. Consider requiring your contractor to provide evidence that subcontractors and suppliers have been paid before releasing the next progress payment.

Monitor the project. Stay involved in the construction process. Attend site meetings, review invoices, and maintain communication with the general contractor about the project's financial status.

Respond promptly to lien notices. If you receive a notice from a subcontractor or supplier asserting a lien claim, consult an attorney immediately. Early intervention can often resolve the dispute before a lien is filed.

Challenging an Invalid Mechanic's Lien

Not all mechanic's liens are valid. Property owners have several potential defenses against lien claims, including that the work was not authorized by the owner, the lien was filed after the six-month deadline, the lien statement contains material errors, the amount claimed is inflated or includes work not performed, the claimant failed to provide required notices under RSMo 429.100 or 429.012, or the general contractor failed to serve the statutory disclosure notice as a condition precedent to their lien.

If you believe a mechanic's lien has been improperly filed against your property, Missouri law allows you to petition the court to discharge the lien. You may also be able to bond around the lien — posting a surety bond that substitutes for the property as security for the claim, allowing you to proceed with a sale or refinancing while the dispute is resolved.

How OTT Law Approaches Mechanic's Lien Cases

At OTT Law, we represent both sides of mechanic's lien disputes. For contractors, subcontractors, and suppliers, we ensure that lien rights are preserved by meeting every deadline, preparing compliant lien statements, and pursuing enforcement when necessary. For property owners, we evaluate the validity of lien claims, negotiate resolutions, and litigate to remove improper liens.

The key in every mechanic's lien case is timing. The statutory deadlines are absolute, and a single missed deadline can eliminate what would otherwise be a valid claim or defense. If you are involved in a construction payment dispute or facing a mechanic's lien claim, consult an attorney as soon as possible.

The financial stakes in construction disputes are often substantial. A contractor who fails to file a timely lien may lose their only meaningful leverage to collect payment. A property owner who ignores a lien notice may find themselves unable to sell or refinance when they need to most. In both cases, whether the underlying issue is a breach of contract or a payment dispute between contractors and subcontractors, early legal counsel is the most cost-effective investment you can make.

Protect what you've built. Schedule a consultation with OTT Law at (314) 710-2740.

Frequently Asked Questions

Can a mechanic's lien be placed on my home for work I did not authorize?

In most cases, no. Missouri's mechanic's lien statute generally requires that the work be authorized by the property owner or the owner's agent. However, if someone with authority over the property — such as a co-owner or a property manager — authorized the work, you may still be subject to a lien. Consult an attorney to evaluate the specific circumstances.

What is the difference between a mechanic's lien and a construction trust fund claim?

A mechanic's lien is a claim against the property itself. A construction trust fund claim is a separate legal theory: Missouri law treats certain construction payments received by a contractor as funds held in trust for the benefit of subcontractors and suppliers. Diverting those funds — for example, using subcontractor payments for personal expenses — can result in personal liability and even criminal exposure under Missouri's stealing statutes.

Can I file a mechanic's lien on a government project?

Generally, no. Government property is typically exempt from mechanic's liens. However, contractors on public projects may have rights under Missouri's public works bond statute (RSMo 107.170), which requires payment bonds on many government construction projects. These bond claims serve a similar protective function for contractors who cannot lien public property.

This article is for informational purposes only and does not constitute legal advice. Every case is different. Contact OTT Law at (314) 710-2740 for a free consultation specific to your situation.

Mechanic's Liens in Missouri