Montana Auto Repair Law

Educational summary only – not legal advice.

Executive Summary

Montana regulates motor vehicle repair shops primarily through the Montana Administrative Rules (ARM Title 23, Chapter 19) and general consumer protection statutes. The law focuses on estimates, authorization, limits on over‑charges, parts return rights, and recordkeeping. While Montana does not require rigid authorization forms, it strictly limits charging beyond estimates without customer consent and treats unauthorized repairs as deceptive trade practices.

This document explains the law in practical terms for both consumers and repair shops.

1. Written Estimates & Dollar Thresholds

What the Law Requires

·       A written estimate must be provided upon customer request for any repair expected to exceed $50.

·       The estimate must include:

o   Labor charges

o   Parts charges

o   Storage charges (if applicable)

o   Approximate completion date

·       Diagnostic fees may be charged only if disclosed when the estimate is requested.

·       Estimates are valid for no more than 5 days unless a shorter period is stated.

If the Law Is Silent

·       Montana law does not require automatic written estimates if the customer does not request one. General consumer‑protection principles still apply.

2. Authorization to Perform Repairs

What the Law Requires

·       A shop may not perform or charge for repairs without customer authorization.

·       Authorization may be written or oral.

·       There is no state‑mandated authorization form.

Best‑Practice Implication

·       Although oral authorization is legal, written authorization is strongly recommended to avoid disputes.

If the Law Is Silent

·       Montana law does not define required language, formatting, or signature requirements for authorization forms.

3. Over‑Estimate Approval Rules

What the Law Requires

·       A repair shop may not exceed the estimate by more than 10% or $25 (whichever is greater) without customer approval.

·       Approval must be obtained before performing additional work.

·       Approval may be oral or written.

Enforcement Impact

·       Charges exceeding the threshold without consent are considered unauthorized and unlawful.

4. Disclosure Timing (Before vs. After Work)

What the Law Requires

·       All required disclosures and approvals must occur before additional work is performed.

·       Consent obtained after the work is completed does not cure a violation.

If the Law Is Silent

·       Montana law does not specify minimum notice timing beyond requiring approval before extra work begins.

5. Parts Return Rules

What the Law Requires

·       If the customer requests at the time the work order is taken, the shop must return all replaced parts.

·       Exceptions:

o   Parts that are impractical to return due to size, weight, or condition

o   Parts required to be returned under warranty or exchange programs

·       If parts must be returned to a supplier, the shop must show them to the customer upon request.

If the Law Is Silent

·       Montana law does not require automatic return of parts unless the customer requests it in advance.

6. Invoices & Record Retention

What the Law Requires

·       Customers must receive a detailed invoice listing:

o   All labor performed

o   All parts supplied

·       Repair shops must retain invoice copies for at least 90 days.

If the Law Is Silent

·       The law does not specify retention periods for estimates, authorizations, or diagnostic records beyond invoices.

7. Prohibited & Deceptive Practices

Montana explicitly prohibits repair shops from: – Charging for repairs not authorized – Misrepresenting the necessity of repairs – Claiming repairs were performed when they were not – Making misleading or deceptive statements

Violations constitute unfair or deceptive trade practices.

8. Enforcement & Consequences

Potential Consequences for Shops

·       Charges for unauthorized work may be unenforceable

·       Exposure to:

o   Consumer restitution claims

o   State enforcement actions

o   Civil penalties under consumer‑protection laws

Consumer Remedies

·       Refusal to pay unauthorized charges

·       Complaints to the Montana Department of Justice

·       Civil claims for deceptive practices

What This Means for Consumers

·       Always request a written estimate for repairs over $50

·       Do not approve open‑ended or vague repair authorizations

·       Explicitly request old parts back when dropping off the vehicle

·       You cannot be charged more than 10% or $25 over the estimate without consent

·       Keep all paperwork

What This Means for Repair Shops

·       Written estimates and documentation protect you

·       Never exceed an estimate without advance approval

·       Clearly disclose diagnostic fees

·       Ask customers upfront whether they want old parts returned

·       Retain invoices for at least 90 days

Bottom Line

Montana auto‑repair law is straightforward but strictly enforced: estimate accuracy, customer consent, and honesty matter more than paperwork formalities. Shops that document approvals and consumers who assert their rights avoid nearly all disputes.

This document is intended as a plain‑English explanation of Montana auto‑repair law and is not legal advice.