Unless you're filing a claim against a government agency or employee, you need not notify the people you think are responsible for your injuries within a set number of days after an accident. But that doesn't mean you should drag your feet. On the contrary, acting right away -- within a few days, if possible -- will increase your chances of receiving a quick and fair resolution to your claim.
Giving notice doesn't obligate you to file a claim; it simply preserves your rights and prevents others from later saying that your claim is unfair because you waited too long to tell them about your injuries. If you promptly notify others that you intend to file a claim for your injuries, you can then move at your own pace in processing and negotiating the claim with the insurance company or government agency that winds up taking responsibility.
For more information, including whom to notify and how to give notice, see the article Personal Injury Claims: Notifying Responsible Parties.
If your accident might have been even partially caused by a government entity or employee -- the city, county, state, or federal government, or any public agency or division (a city bus or a school district, for example) -- you must file a formal claim within a short time after your accident. This period of time usually ranges between 30 days and one year, depending on your state. If you fail to file a claim within the time limit, or fail to include required information in your claim, you may forever lose your right to collect compensation.
To find the time limit for your state, call your city or county attorney's office and ask. Although they may be the ones defending against your claim if you file it, they are under a legal obligation to give you correct filing information.
You can also find a complete list of time limits, plus instructions on how to file a government claim, in How to Win Your Personal Injury Claim, by Joseph Matthews (Nolo).
If you have no success reaching a settlement with an insurance company, you may be forced to consider bringing a lawsuit in small claims or other court. But you must be aware of the laws, called "statutes of limitations," that limit the time in which you have to file. If you miss your state's deadline, you will lose your right to recover compensation in court, and will be forced to abandon your claim altogether.
Check your state's laws to find the time limit that applies to your case. You can find a list of the statutes of limitations for all 50 states in the article Statutes of Limitations: Is It Too Late to Sue?
There are a number of things you can do in the first few days and weeks after an accident to protect your right to compensation should you want to file an injury claim. Except for filing a formal claim against a government entity, there's no single step that you absolutely must take to obtain a fair settlement, and no set order in which you must proceed. However, the more of the following suggestions you can follow, the more smoothly your claim process is likely to flow.