There is no single deadline after a car accident. There are several, they run at the same time, and the shortest one is usually the one people have never heard of. Missing any of them can end a claim regardless of how strong it was.
I am not a lawyer and this is general information, not legal advice. Laws and insurance practice vary by state. Speak to an attorney licensed in your state about your own situation.
Deadline one: telling your own insurer
Your policy requires prompt notice of an accident. This is a contractual deadline, not a legal one, and it is often measured in days. Late notice can give your insurer grounds to deny coverage, including coverage you may need later, such as uninsured motorist benefits.
Notify your own insurer even if the crash was not your fault and even if you do not intend to claim on your policy.
Deadline two: notice to a government entity
This is the one that catches people out. If a government vehicle, employee, or a publicly maintained road was involved, a formal written notice of claim is usually required long before any lawsuit, and the window is frequently a matter of months rather than years.
Miss it and the claim is generally barred even though the ordinary filing deadline has years left to run. If any government entity might be involved, treat this as your real deadline and act immediately.
Deadline three: the statute of limitations
This is the deadline to file a lawsuit, set separately by each state. It varies considerably, from one year in a few states to six in others, and it is the deadline most people mean when they ask this question.
Two things about it are commonly misunderstood. Settlement negotiations do not pause it, so a claim can be actively under discussion right up to the point it becomes unenforceable. And filing an insurance claim is not the same as filing a lawsuit; only the lawsuit stops the clock.
When the clock starts
Usually the date of the crash. Most states also recognise a discovery rule, which delays the start where an injury could not reasonably have been discovered at the time. This matters for injuries that surface later, but it is an exception rather than a default and should not be relied on casually.
Situations where the deadline shifts
- Injured minors. In many states the clock does not begin until the injured person turns eighteen.
- Wrongful death. Often runs from the date of death rather than the date of the crash.
- The defendant leaves the state. Some states pause the period during absence.
- Fraudulent concealment. Where a defendant hid their involvement, many states delay the start.
- Claims against your own insurer. Uninsured and underinsured motorist claims run on policy terms that may differ from the statutory deadline. See uninsured and underinsured claims.
Why waiting costs you even inside the deadline
Being technically in time is not the same as being in a good position. Evidence degrades, vehicles are repaired or scrapped, witnesses become unreachable, and a delay between the crash and your first medical visit is used to argue you were not really hurt. See why delayed treatment damages claims.
There is also the practical point that claims take months to resolve once started. See how long settlements take.
What to do
Find out the deadline that applies in the state where the accident happened, not where you live. Check whether any government entity was involved. If a deadline may be close, speak to an attorney licensed in that state now rather than researching further, because an attorney can file to preserve the claim while the details are worked out.