Chances are that deciding when to claim Social Security likely will be one of the biggest retirement choices you will ever make.

Yet a recent survey from MassMutual found that many pre-retirees are getting key facts about the program’s rules wrong — and just one mistake can hurt you financially.

The firm recently gave a 12-question true-or-false quiz to 1,500 people ages 55 to 65 who have not yet claimed their benefits.

Just 54% of respondents were able to correctly identify whether their benefits will continue to increase if they delay claiming retirement benefits past age 70. The answer is no.

Moreover, if you delay past 70, you can only go back six months to make up for lost monthly checks, said David Freitag, a financial planning consultant and Social Security expert at MassMutual.

“The benefits that they have missed, they’re never going to see,” he said.

Overall, the results showed that 35% of the respondents failed the quiz altogether, and 18% received a grade of “D.”

Just 3% of the respondents were able to answer all of the questions correctly.

Certain questions tended to stump people more.

Survey respondents were generally unable to distinguish the rules for spousal benefits after divorce and survivor benefits after the death of a spouse.

The results showed that 22% of near-retirees did not know that if a spouse passed away you cannot collect both your own and your spouse’s benefits. (Typically, you get either yours or your spouse’s, whichever is higher).

Meanwhile, 30% of respondents did not know that they might be able to claim benefits on their ex-spouse’s work record. (You must have been married for at least 10 years, among other qualifications.)

Each of those benefits comes with distinct rules, Freitag said, which means it’s important to understand them before claiming.

“Although survivor benefits sound like spousal benefits, they’re totally different,” he said.

The results were not all bad.

Most respondents — 94% — were able to correctly say that their retirement benefits will be reduced if they claim them before full retirement age (generally 66 or 67, depending on your year of birth).

A majority — 86% — were also able to accurately affirm that their Social Security benefits may be reduced if they collect their monthly checks before full retirement age and continue to work.

Curious to see how well you would do on the quiz? Decide whether each statement below is true or false, then check your responses against the answer key below.

1. If I take benefits before my full retirement age, they will be reduced for early filing.
2. If I am receiving benefits before my full retirement age and continue to work, my benefits might be reduced based on how much I make.
3. Once I start collecting Social Security, my benefit payments will never change.
4. If I have a spouse, he or she can receive benefits from my record even if he or she has no individual earnings history.
5. If I have a spouse and he or she passes away, I will receive both my full benefit and my deceased spouse’s full benefit.
6. The money that comes out of my paycheck for Social Security goes into a specific account for me and remains there, earning interest, until I begin to receive Social Security benefits.
7. Under current Social Security law, full retirement age is 65 no matter when you were born.
8. As a divorced person, I might be able to collect Social Security benefits based on my ex-spouse’s earnings history.
9. Under current law, Social Security benefits could be reduced for everyone in 2035.
10. If I file for retirement benefits and have dependent children age 18 or younger, they also may qualify for Social Security benefits.
11. If I delay taking Social Security benefits past the age of 70, I will continue to get delayed retirement credit increases each year I wait.
12. I must be a U.S. citizen to collect Social Security retirement benefits.

Answers:

1. True
2. True
3. False
4. True
5. False
6. False
7. False
8. True
9. True
10. True
11. False
12. False