It sounds like a scam. You receive a letter from a private company saying you are owed thousands of dollars in unclaimed money. The company would be willing to secure the funds for a 30 percent fee. Yes, it seems sketchy. But do you really have money out there?

It’s actually quite likely that you do.

Unclaimed money is your money that’s been misplaced: things like final paychecks you never cashed, apartment security deposits that weren’t returned to you, and life insurance policies left to you by deceased loved ones — and so on. What these opportunistic companies do is scan lists of people owed unclaimed money and then contact them in hopes of getting a cut. But why not lose the middle man? You can claim this money yourself without having to pay anybody a percentage.

You only need to check two websites to access any of the $42 billion in unclaimed money held by the 50 states, the District and several Canadian provinces. First go to missingmoney.com and fill in your name and the state where you live. The site will then automatically check all 39 states with which it has a relationship. If you don’t see your unclaimed property listed there, you will need to search the other 11 states individually — Arkansas, California, Connecticut, Delaware, Georgia, Hawaii, Illinois, New York, Oregon, South Carolina and Wyoming. You can do that at unclaimed.org. (Important note: The free website ends in “.org.” If you accidentally type in “.com” you will land on a page that charges money to search.)

Unclaimed money is typically held in a state where you have lived, but it can also be kept in the state where the financial institution has offices, which is why checking all 50 states is a smart move.

The entire search process takes about five minutes, and yet so few people even try. The average claim is for $892, according to the National Association of Unclaimed Property Administrators. That’s real money.

I encourage you to try an unclaimed money search today — and then recheck every year. Why the urgency? States are shortening the amount of time you have to claim this money because it helps them balance their budgets. Twenty-seven states plus the District now force financial institutions to turn accounts over to them if you have been out of touch for just three short years. And states are not always the best stewards of your money. They don’t pay interest on it while they hold it, and some sell off assets such as stocks, bonds and valuables from safe-deposit boxes for a fraction of their true value.There’s one final reason to get on this project now: The longer you wait to make a claim, the harder it is to pull together the documentation you need to prove you are the rightful owner of that unclaimed money.

One of the most common pieces of documentation you need to successfully wrest your unclaimed money from the state is something that shows past addresses where you have lived. That’s because unclaimed money is typically filed by name and verified by address. Most of us don’t keep old utility bills or other paperwork that proves where we lived years ago. So here’s a hot tip: Obtain your credit reports from AnnualCreditReport.com. That’s the free website set up by Congress. Credit reports almost always list your past addresses going back decades and should provide the proof you need to file your claim.

Elisabeth Leamy is a 13-time Emmy winner and 25-year consumer advocate for programs such as “Good Morning America” and “The Dr. Oz Show.” Connect with her at leamy.com and @ElisabethLeamy.