No, your new insurance policy will not cover your accident that took place before the inception or reinstatement of your policy. Any pre-existing damage to your vehicle would not be covered by your collision coverage nor would any damages you caused to others be covered by your liability coverages since your policy was not in place at the time of accident.

Any reputable insurance company would not backdate your policy to cover these damages either. In fact no auto insurance company should backdate a car insurance policy period. In general backdating the effective date of an auto insurance policy is not permitted.

If an insurance carrier would backdate the start date of a policy this would inevitably favor the insured, because it opens the insurance company to risk. For example a person could have been in an accident during this time and though they did not have insurance now try to claim it if the insurance was post-dated or backdated.

While having an insurance policy in place may help you legally in court if you were charged with driving without insurance, however you still will likely be held personally responsible for the damages you caused to the car you crashed into and any bodily injuries you may have caused. If this was a severe accident you may need to seek legal counsel.