If you are driving and you are in an accident, expect your auto insurance rates to go up. That's most likely going to happen regardless of whether you are found to be at fault.
Why Does A Not-at-Fault Accident Affect My Premiums?
A car insurance provider's business model is built around risk. Higher premiums are not necessarily a reflection on you as a driver. Rather, they are a reflection of risk. The accident may have been someone else's fault or it may be quite clear that another driver was being reckless. But the fact that you were in an accident in the first place tells your insurance provider that there is some additional risk they should account for. Whether you live near a bar or off of roads that are dangerous when wet, your insurer is taking into account that, in some way or other, your risk is a little higher than your existing premiums reflect.
Consider also that if you carry uninsured driver coverage, your insurance company needs to take responsibility for that cost, and calculate it into the risk that they're taking.
How Long Will I Be Paying For The Accident?
Typically, higher premiums will last for about three years. The rate by which your premiums will be bumped will vary from one auto insurance provider to the next, so it would be difficult to give an accurate estimate as to the percentage by which you can expect your premiums to climb following an accident.
Is There Any Way To Bring My Premiums Back Down?
Because the not-at-fault accident was, by definition, not your fault, it may actually be difficult to negotiate with your insurer on this matter. What you can do is seek for discounts to offset the difference. Ask your insurer what you can do to bring your rates down. Options abound, from advanced driving courses to safety-device discounts.
It is unfortunate that a not-at-fault accident will bump your rates, but car insurance companies do need to manage their own risk, as well as cover your losses. Fortunately, the bumped premiums only last a few years, and you may be able to offset the additional cost with discounts offered by your provider.