Each state has a time limit, or statute of limitation, as to when a small claims case can be filed.
For instance, if your neighbor owed you money 20 years ago, you cannot file a small claim today for that money. The statute of limitation has expired.
Time limits differ by state depending on the type of claim. The statute of limitation for written contract disputes is often longer than for personal injury claims.
See the chart below for the statute of limitations (in years) for some typical cases.