Unless you’ve managed to avoid borrowing money in the past 21 years — we’re talking everything from credit card purchases to buying a home — you’re probably eligible for a class action settlement that TransUnion is offering.

TransUnion is offering free credit-monitoring services to settle the claims that the company had illegally distributed private information about consumers for marketing purposes. TransUnion continues to deny any wrongdoing, but millions of U.S. consumers are eligible for this settlement. The settlement gives consumers the ability to sign up for either six or nine months of credit monitoring. The eligibility criteria is extremely broad: if you had any open credit account or line of credit between Jan. 1, 1987 and May 28, 2008. More than 150 million consumers are eligible for this settlement, and the law firm representing the plantiffs in the class-action suit against TransUnion says that fewer than 400,000 have signed up for the settlement so far.

The deadline to take advantage of this settlement is Sept. 24. To register, you’ll need to visit the site established to manage the settlement or call 866-416-3470. Remember, if you decide to take advantage of this settlement and you are married, your spouse will need to register — even if you share joint credit accounts, both you and your spouse have separate credit reports.

The settlement has not yet been finalized, and won’t be until after Sept. 24. When you register, you’ll have the option of selecting between four ‘payments’:

• Six months of credit monitoring.
• A cash payment (if money is available for distribution).
• Six months of credit monitoring and a potential cash payment.
• Nine months of enhanced monitoring service. (If you select this option, you can’t get any cash.)

Before you leap at that cash payment, you should know that it won’t be available utnil at least two years after the settlement is finalized by the court — if ever. And we’re certainly not talking about much money. TransUnion has agreed to pay $75 million into the settlement fund. Out of that, $150,000 immediately goes to nonprofit organizations. Then the lawyers’ fees, as well as any other fees or expenses, are paid out. Then, judgements and settlements for individual damage claims will be paid. Last in line are the regular consumers who register for the settlement. Even if you wait the full two years, there is no guarantee that you’ll get an actual check out of it. The price of TransUnion’s credit monitoring service for six months is $59.75. The nine-month version retails for $115.50. You’ll be able to start your six (or nine) months of credit monitoring just six months after the settlement is finalized. As long as you will use it, the credit monitoring option is probably the best bet.

During the time you will be covered by the credit-monitoring plan, you’ll be able to keep a closer eye on your credit than normal, allowing you to theoretically catch identity theft and fraud before it becomes a major issue. TransUnion notifies you of any major changes to your credit report within 24 hours, as well as allows you to lock your credit report. But remember, credit monitoring is meant to help you spot fraud and other problems — not prevent it.