Montana Property Posting Guide: Regulations and Requirements

In Big Sky Country, a fence line doesn't always mean "keep out." Unlike many states where private property is automatically off-limits, Montana law operates on a unique presumption of access. If you haven't explicitly told the public to stay out, the law often assumes they have the "privilege" to enter.

This makes effective signage more than just a formality—it is the only legal way to revoke that privilege and ensure the Sheriff can enforce your boundaries.

To protect your land under Montana Code Annotated (MCA) § 45-6-201, you must meet specific posting standardards. Here is the breakdown of what is required to legally post your property.

The "Implied Privilege" Rule (Why You MUST Post)

Unlike some states where a fence or a crop line automatically revokes public access, Montana operates on a concept of "privilege."

The Rule: Under MCA § 45-6-201(1), privilege to enter private land is extended to the public by the failure of the landowner to post notice.

The Reality: If your land is not posted with signs or orange paint, a person generally does not commit criminal trespass by entering until you personally ask them to leave. To revoke this privilege before they enter, you must post your land legally.

(Note: There is a strict exception for hunting. Under MCA § 87-6-415, hunters must always obtain permission to hunt on private land, regardless of whether it is posted.)

How to Post Legally (Paint vs. Signs)

To effectively revoke the public's privilege to enter, you must provide "effective posting" using one of the following methods:

Option A: Fluorescent Orange Paint Montana recognizes specific paint markings as legal notice.

Color: Must be fluorescent orange.

Size: The mark must be at least 50 square inches.

Placement: If using a metal fence post, the entire post must be painted. If using a tree or wood post, the 50-square-inch mark must be clearly visible.

Option B: Written Notice (Signs) Signs are often preferred for removing ambiguity.

Placement: Notice must be placed at each outer gate and normal point of access to the property.

Waterways: You must post on both sides of a water body wherever it crosses your outer boundary line.

The "Public Road" Requirement

If your land borders a public road (and is unfenced or has an unfenced right-of-way), the law requires more frequent notification to prevent accidental trespass from the highway. You must either:

1. Post a Sign: Place a conspicuous sign no closer than 30 feet from the roadway centerline stating: "PRIVATE PROPERTY, NO TRESPASSING OFF ROAD NEXT [X] MILES."

2. Interval Posting: Place signs or orange paint (no closer than 30 feet from centerline) at regular intervals of not less than 1/4 mile (1,320 feet) along the roadway.

What Must the Sign Look Like?

While Montana law allows for orange paint, using a sign provides clearer legal standing by explicitly stating the prohibition.

Legibility: Signs must be "conspicuous" and legible. While the statute does not mandate a specific font size for general posting, standard practice to satisfy the "written notice" is to have wording that a reasonable person can read from the access point.

Content: The sign should clearly state "No Trespassing" or similar language prohibiting entry. Including the landowner's name and contact information is recommended but not explicitly demanded by the criminal trespass statute (though it is helpful for law enforcement).

Penalties

When land is posted according to these standards, entering without permission becomes Criminal Trespass to Property.

Fines & Jail: A person convicted can be fined up to $500 and imprisoned in the county jail for up to 6 months.

Hunting Revocation: If the trespass involves hunting, fishing, or trapping, the offender faces the revocation of their hunting/fishing privileges.

Summary

In Montana, an unposted fence is often seen as an "open door" in the eyes of the law. To protect your property rights and ensure the Sheriff can cite trespassers, you must explicitly revoke public privilege by posting fluorescent orange paint or conspicuous signs at all gates, access points, and water crossings.

If you need compliant signs that will outperform your standard hardware store signage, check out BOUNDARYSIGN.