7 On Your Side: When not to give out your Social Security number

The Federal Government's Office of Personnel Management has completed its long awaited damage assessment after being hit by suspected Chinese hackers. Sources tell ABC News that more than 25 million people inside and outside the government likely had their information stolen. That amount is more than six times what was originally announced a month ago.

These kinds of data breaches show how vulnerable social security numbers are to hackers. 7 On Your Side is partnering with Consumer Reports with important advice on how you can protect your social security number.

Paying taxes, getting a job, accessing government benefits, opening a bank or credit card account, going to the doctor, buying a car all may require that you reveal your social security number.

Data security expert and co-founder of Credit.com Adam Levin says it can be a disaster when that number falls into the wrong hands.

"The Social Security number is the mother lode for an identity thief. This is the pot of gold at the end of the rainbow because you can do so many things with it," Levin said.

For example, opening credit-card accounts in your name or stealing your tax refund.

Consumer Reports' Margot Gilman says one way to protect yourself is don't give out your social security number just because you're asked for it.

"Only share your Social Security number with those you choose and who absolutely need it, like potential creditors or employers," Gilman said.

Surprisingly, doctors don't need your social security number, even though they often ask for it.

Unless you're covered by Medicare, you can leave that spot on medical forms blank and most health care providers won't question you.

"We don't require patients to give us their Social Security number because they give us their insurance card, which has their policy number on it, and we can get all the information and verification that we need from that," medical office receptionist Jillian Korr said.

Even Medicare is moving to drop social security numbers from its cards and replace them with another type of identifier.

Another place you don't need to give up your social security number when asked is at school. That request often comes when kids enroll or register for sports or other after school activities.

It is important to check for suspicious activity each year by getting your annual free credit report at AnnualCreditReport.com.