More and more Americans are complaining about fraudsters hijacking their identities, according to data from the Federal Trade Commission. The agency received more than 490,000 identity theft complaints in 2015, a nearly 50 percent jump from 2014.

Identity theft has long topped the list of complaints received by the consumer watchdog agency. But the FTC ­complaints barely scratch the surface of America’s identity theft problems.

The Department of Justice estimates 17.6 million Americans aged 16 or older were victims of at least one attempt of identity theft in 2014. But less than 1 percent of victims said they turned to the FTC, according to the DOJ survey. And fewer than one in 10 said they reported the incident to police.

If identity theft is such a big problem, why do so few people ask the government for help? To answer that question, we need to talk a bit about what identity theft means — and who foots the bill.

Identity theft can take many forms. But by far the biggest chunk of incidents in the United States involves someone trying to hijack an existing bank or credit card account. Because of this, financial institutions and credit card companies invest heavily in detecting fraud — and they often give a guarantee that ­consumers won’t be responsible for fraudulent activity on their accounts.

The end result is that very few ­identity theft victims end up on the hook for the cost of the crime: Just 7 percent of victims told DOJ that identity theft cost them more than $100.

Of course, it’s not always that easy, ­especially for people dealing with other types of identity theft. If a criminal opens up a new account using another person’s name, it can leave a web to untangle.

But there are some steps you can take to avoid getting caught up in new ­account fraud. One tactic is to freeze your credit — a process where you ­typically pay a few dollars to lock down your credit report so it can’t be accessed unless you’ve contacted the credit reporting agency to temporarily thaw it out.

The FTC’s site, IdentityTheft.gov, can help victims mitigate some of the damage — walking consumers through steps like placing fraud alerts on accounts, reporting incidents to law enforcement, and freezing their credit.