Filing a claim

What happens if I was partially at fault in the accident?

What shared fault means

Shared fault means both drivers contributed to the crash. One driver may have run a stop sign while the other was traveling faster than conditions allowed. One may have changed lanes without checking while the other was following too closely to stop. Most real crashes have more than one cause, and the claim process is built to deal with that: instead of an all-or-nothing verdict, fault is divided into percentages that add up to the whole.

That split matters because it is applied to money. The percentage assigned to you is not just an opinion about the crash — in most states it directly reduces, and in some situations eliminates, what the other side has to pay you. It is worth understanding which rule your state uses before you talk numbers with any adjuster.

The three rule families

States handle shared fault in three broad ways. The details are each state's own, and this page deliberately does not list which states use which rule — confirm yours with your state insurance department or a primary source before you rely on it. The families are:

Pure comparative fault. Your recovery from the other side is reduced by your percentage of fault, and that is the whole rule. If you were a small share at fault, you lose a small share of the recovery; if you were mostly at fault, you can still recover the remaining share from the other driver. There is no cutoff point where the claim disappears.

Modified comparative fault. Your recovery is reduced by your percentage of fault the same way, but only up to a threshold. Once your share of fault reaches the state's threshold, you are barred from recovering from the other side at all. States set that threshold in one of two places: some set it at half, so a driver who is half or more at fault recovers nothing; others set it just past half, so a driver who is exactly half at fault can still recover the other half. A single percentage point can decide the whole claim under this rule, which is why the exact percentage matters so much.

Contributory negligence. A few states still use this older, stricter rule. If you share any fault for the crash — even a small share — you are generally barred from recovering from the other driver at all. In these states the fight is not over how large your percentage is but over whether you have one.

How shared fault changes each claim

A third-party claim against the other driver shrinks. What you can recover from the other driver's liability insurer — repairs, rental costs, diminished value, and other losses their driver caused — is reduced by your percentage under the comparative rules, or barred under the threshold and contributory rules. The diminished value piece follows the same math as the rest of the property claim; it is covered in Who pays diminished value — my insurer or theirs?

Your own collision claim still responds. Collision coverage pays for damage to your own car regardless of who caused it, within the policy's terms. Being partly at fault does not usually switch it off. You pay your deductible, and if your insurer later recovers from the other side, you may get some or all of that deductible back — but the repair itself does not have to wait for the fault argument to end.

Injury claims follow the same reduction logic. Where an injury claim is made against the other driver, the same shared-fault rule generally applies to it: reduced by your percentage under a comparative rule, barred at the threshold or by any share of fault under the stricter rules. Injury claims raise medical and legal questions beyond the scope of this guide; the fault math described here is the part that works the same way.

How the percentage gets set

No instrument measures fault. The percentages are an assessment: adjusters review the evidence — the police report if one exists, photos and video, statements from both drivers and any witnesses, and the damage patterns on the cars — and form a position on how the fault divides. Each insurer forms its own position, and the two positions often differ.

Because the number is assessed rather than measured, it is frequently negotiated. An opening position from the other insurer is exactly that — a position. It can move when the evidence behind it is challenged with better evidence. That is the practical reason to build your evidence file early, as described in How do I prove fault when filing a car accident claim?

What to do with a percentage you dispute

1. Get the position in writing. The percentage, the rule they say applies, and the evidence they relied on. You cannot answer a position you cannot read.
2. Answer with evidence, not outrage. Respond in writing, point by point, with the photos, statements, report details, or damage evidence that support a different split. Percentages move when the evidence behind them changes.
3. Keep your own collision option open. If the dispute will drag on and your car needs repair, your own collision coverage can get the car fixed while the fault argument continues, minus your deductible.
4. Use the dispute path if it stalls. A written complaint to your state insurance department, and the steps in the dispute and appeal guide, are the next level when an insurer will not move or will not explain itself.

Frequently asked questions

If I am 20 percent at fault, what happens to my claim?

Under a comparative fault rule, your recovery from the other side is reduced by your share. As a hypothetical example, a $10,000 loss with 20 percent fault assigned to you would be reduced by 20 percent, leaving $8,000 recoverable from the other driver's insurer. Under a modified rule, 20 percent sits below the usual thresholds, so the claim is reduced rather than barred. Under contributory negligence, which a few states still use, sharing any fault can bar recovery entirely.

Can I still file on my own collision coverage if I was partly at fault?

Yes. Your own collision coverage generally responds to damage to your car regardless of how fault is divided, minus your deductible. Fault mainly controls what you can recover from the other driver's insurer. Claiming on your own collision coverage can also get repairs moving while the fault split is still being argued.

Who decides the fault percentages?

For claim purposes, the adjusters do. Each insurer reviews the evidence and forms a position, and the percentages are often negotiated between the insurers, or between you and the other insurer. It is an assessment based on the evidence, not a measurement, and if the sides cannot agree, a court is the backstop that can decide it.

Can I dispute the percentage they assigned me?

Yes. Ask for their position and the evidence behind it in writing, then respond in writing with the evidence that supports a different share, such as photos, witness statements, the police report, or the damage patterns. Percentages move when the evidence changes, so lead with evidence rather than opinion, and keep copies of everything you send.