The national Personal Auto Policy guide covers the ISO policy. This guide covers the Missouri rules around it:

• the Motor Vehicle Safety Responsibility Law (RSMo chapter 303)
• required uninsured motorist coverage and the underinsured motorist excess rule (379.203, 379.204)
• the Department's auto policy standards (20 CSR 500-2.100)
• the auto cancellation law (379.110–379.120)

Missouri is an at-fault (tort) state. Liability insurance responds to damages imposed by law, and there is no PIP or no-fault threshold.

Financial responsibility (RSMo chapter 303)

• After an accident involving injury, death or more than $500 of property damage to any one person, an uninsured driver's license is suspended within 90 days unless security is deposited (303.030).
• A suspended driver must keep proof of insurance for 3 years after the suspension (303.044).
• Certified policies: 20 CSR 500-2.300 says a certified policy is documented by filing a form, typically an SR-22, with the Director of Revenue. It's ended by an SR-26.
  • Certified coverage can't be cancelled until at least 10 days after the SR-26 is filed.
  • The SR-22 filing fee may be charged only once for the certified period.

What the owner's policy must do (303.190)

• Cover the named insured and anyone using the vehicle with express or implied permission.
• Cover use in the U.S. and Canada.
• It may exclude a specifically named household driver.
• The insurer's liability becomes absolute when a covered injury occurs. A binder satisfies the requirement for a policy.

Uninsured and underinsured motorist coverage

• UM is required in every policy on a vehicle registered or principally garaged in Missouri. Limits must be at least the bodily injury minimums (379.203).
  • For commercial vehicles and fleets of 5 or more passenger vehicles, it need only be offered.
  • UM applies to hit-and-run vehicles whether or not there was physical contact.
  • It applies to vehicles whose insurer becomes insolvent within 2 years of the accident.
• UIM with limits less than twice the bodily injury minimums must be treated as excess over the at-fault driver's liability coverage (379.204).
• UM coverage may not (20 CSR 500-2.100):
  • set off medical payments or workers' compensation
  • force arbitration
  • narrow the statutory definition of an uninsured vehicle

Policy standards (20 CSR 500-2.100)

• "Insured" must include the resident spouse and permissive users.
• A newly acquired or replacement auto gets at least 30 days to be reported.
• Territory: at least the U.S., its territories and possessions, and Canada.
• Transportation expense coverage: a waiting period of no more than 48 hours, and at least $10 a day up to at least $300.
• Medical payments can't be excess over other health coverage unless clearly disclosed and reflected in the rate.
• Physical damage can't exclude factory-installed equipment.
• Driver exclusions apply only to the named person, with the named insured's signed acknowledgment.

Cancellation and nonrenewal (379.110–379.120)

• Scope: private passenger policies in effect more than 60 days or renewed. The law doesn't apply to plan policies, policies on more than 4 vehicles, or garage risks.
• Cancellation reasons (379.114): only nonpayment, or suspension or revocation of the named insured's license.
  • If only one of several named insureds has a suspended license, the insurer can't cancel. It may issue a named exclusion instead.
• No refusals based on age, residence, race, sex, color, creed, national origin, ancestry or lawful occupation alone. An insurer can't ask whether another insurer refused the applicant.
• Notice (379.118):
  • At least 30 days for cancellation or nonrenewal, or 10 days for nonpayment.
  • Sent with a certificate of mailing or other USPS tracking.
  • The notice must give a specific reason. "Violation or accident record" isn't specific enough.
  • It must mention the Missouri Automobile Insurance Plan.
• Renewal and coverage reductions: a renewal notice goes out at least 15 days before the new policy takes effect. Notice of a coverage reduction comes at least 15 days ahead or with the renewal notice. An insurer-mandated reduction that isn't applied to everyone on the same form is treated as a nonrenewal.
• An insurer that refuses an applicant must explain the actual reason in writing within 30 days if asked (379.120).
• A policy shorter than 6 months counts as written for successive 6-month periods.

Missouri Automobile Insurance Plan (303.200)

• Every insurer actively writing auto liability in Missouri participates.
• The plan provides policies for applicants who are entitled to coverage but can't get it normally.
• Members are assessed in proportion to their voluntary market share.

Ridesharing and car sharing

• TNC drivers (379.1702):
  • Logged on and waiting: at least 50/100/25.
  • During a ride: $1,000,000.
  • The TNC's coverage pays from the first dollar if the driver's coverage lapses.
• Peer-to-peer car sharing: the program's insurance is primary during the sharing period (379.1915). The owner's personal insurer may exclude that period (379.1925).

Common exam traps

• Minimums: 25/50/25. UM at the same 25/50 is required.
• UIM below twice the minimums is excess.
• Missouri has no PIP and no no-fault threshold.
• Cancellation after 60 days: only for nonpayment or license suspension. Notice: 30 days, or 10 for nonpayment.
• New autos get at least 30 days to be reported.
• SR-22 to certify. SR-26 to cancel, with 10 days' notice.