Missouri Lemon Law, explained for vehicle owners.
The Missouri Lemon Law — formally the New Vehicle Warranty Act, codified at RSMo § 407.560-579 — gives Missouri vehicle owners the right to a refund or replacement after four repair attempts for the same defect or 30 working days out of service during the express-warranty period or one year, whichever first occurs. Missouri does not operate a state-administered arbitration program; consumers proceed through manufacturer arbitration (where available) or directly to court. The Missouri Merchandising Practices Act (MMPA, RSMo § 407.020) overlays as broader consumer-protection remedy with attorney-fee shifting.
Missouri's Lemon Law is one of the simpler state frameworks in the country — no state arbitration program, no procedural prerequisites, just the basic Lemon Law presumption combined with Missouri's general consumer-protection statute. The simplicity is consumer-friendly when paired with the Missouri Merchandising Practices Act, which provides attorney-fee shifting and a longer statute of limitations than the standard UCC warranty period. The combination makes Missouri a relatively favorable venue for Lemon Law cases despite the absence of a dedicated state arbitration program.
This is general legal information, not legal advice. Consult a licensed Missouri attorney for advice on your specific situation.
Missouri Lemon Law structure
The Missouri Lemon Law is codified at RSMo § 407.560-579, formally the New Vehicle Warranty Act. Key features:
- No state arbitration program: Missouri does not operate state-run Lemon Law arbitration
- Manufacturer arbitration option: Use BBB Auto Line or other certified programs where available
- Court alternative: Direct civil action in Missouri Circuit Court
- Attorney-fee shifting: Recoverable through MMPA in court actions
- Coverage period: Express warranty period or 1 year, whichever first occurs
What vehicles are covered
Missouri Lemon Law applies to:
- New motor vehicles purchased or leased in Missouri for personal use
- Demonstrator vehicles sold to consumers
- Vehicles used primarily for personal, family, or household purposes
Used vehicles, motor homes (living quarters), and commercial vehicles over the consumer-use threshold generally are excluded. Federal Magnuson-Moss may still apply to written warranties on used vehicles.
Repair-attempt thresholds
Missouri uses "working days" for the days-out-of-service count. Working days exclude weekends and Missouri legal holidays. The life-threatening defect exception lowers the count to one repair attempt for defects that pose substantial risk of death (brake failures, fuel leaks, fire hazards).
Missouri Merchandising Practices Act overlay
Codified at RSMo § 407.020 et seq. A broader Missouri consumer-protection statute that overlays the Lemon Law and provides remedies for unfair, deceptive, or unconscionable practices in merchandise sales, including vehicles. Allows attorney-fee shifting, punitive damages, and a 5-year statute of limitations.
The MMPA gives Missouri consumers significant additional leverage:
- Punitive damages for willful or wanton conduct
- Attorney-fee shifting to prevailing consumer (RSMo § 407.025(2))
- 5-year statute of limitations from accrual
- Court-only filing in Missouri Circuit Court
Missouri consumer-warranty attorneys typically file Lemon Law and MMPA claims together for procedural redundancy and broader damage exposure.
Remedies under Missouri law
- Refund: Purchase price + collateral charges − usage offset
- Replacement: Comparable new vehicle with usage offset
- Attorney fees: Recoverable through MMPA
- Punitive damages: Available for willful conduct under MMPA
For full calculation methodology, see our buyback and replacement guide.
Filing deadlines
- Missouri Lemon Law coverage window: Express warranty period or 1 year, whichever first occurs
- Court statute of limitations (warranty): 4 years (RSMo § 400.2-725)
- MMPA statute of limitations: 5 years from accrual
The MMPA's 5-year period gives Missouri consumers an extra year compared to the UCC warranty SoL. For comprehensive deadline analysis, see our statute of limitations guide.
Step-by-step Missouri claim process
- Defect manifests during express warranty period or first year
- Document repair attempts (each repair order, dates, mileage)
- Reach repair-attempt threshold (4 same-defect, 1 life-threatening, or 30 working days)
- Send written notice to manufacturer demanding cure
- Optional: try manufacturer arbitration if available (BBB Auto Line for participating manufacturers)
- If unresolved, file civil action in Missouri Circuit Court (typically county of residence or sale)
- File parallel MMPA claim for treble-damages exposure
- Discovery, mediation, settlement or trial
Major Missouri metros
Top Missouri vehicle markets:
- St. Louis (~2.8M metro population, including Illinois suburbs)
- Kansas City (~2.2M metro population, including Kansas suburbs)
- Springfield (~470K metro population)
- Columbia (~210K metro population)
Missouri's two major markets are bistate metros — the St. Louis area extends into Illinois and Kansas City into Kansas. Vehicle purchases sometimes cross state lines, raising venue questions for Lemon Law claims.
Frequently asked questions
Does Missouri have a state-run Lemon Law arbitration program?
No. Missouri does not operate a state arbitration board. Consumers can use manufacturer-sponsored arbitration (like BBB Auto Line) where available, or proceed directly to court.
Should I file a Missouri Lemon Law and MMPA claim together?
Most Missouri consumer-warranty attorneys file both. The Lemon Law provides refund/replacement; the MMPA adds punitive-damages exposure for willful manufacturer conduct and a 5-year statute of limitations. The combination significantly expands settlement leverage.
What if I bought my vehicle in Kansas City, Kansas instead of Kansas City, Missouri?
The state of purchase matters for which state's Lemon Law applies. Vehicles purchased in Kansas are governed by the Kansas Lemon Law; vehicles purchased in Missouri by the Missouri Lemon Law. If you purchased in Kansas but reside in Missouri, complex jurisdictional analysis applies — consult an attorney familiar with bistate metro disputes.
Does the Missouri Lemon Law cover used cars?
Generally no — Missouri Lemon Law applies to new vehicles only. CPO vehicles sold with manufacturer warranty may qualify in limited circumstances. For used vehicles, federal Magnuson-Moss and Missouri MMPA remain available paths. See our used-car coverage guide.
What is the difference between "working days" and "calendar days"?
Missouri counts "working days" — meaning weekends and Missouri legal holidays are excluded. A vehicle in the shop from Friday through Tuesday counts as 1 working day (Friday) plus zero for the weekend. Memorial Day, Independence Day, and other state holidays also do not count.
Next steps
- Read the general Lemon Law overview for federal context
- Document repair history meticulously starting now
- If approaching the 1-year coverage window, consult a Missouri consumer-warranty attorney
- Consider combined Lemon Law + MMPA strategy for punitive-damages exposure
- If you find an error in this guide or want us to add a citation, tell us
This guide is reviewed quarterly against current Missouri statutes. Last full review: May 2, 2026.