Uncertainty can be a dangerous thing. If you're trying to plan for retirement, for example, it can be hard to determine how much you need to amass before retiring without knowing, for example, how much you should expect from Social Security.

Fortunately, the size of your future Social Security checks isn't a total mystery. Here's a look at what you might expect if you're earning $100,000 -- along with guidance on how to find out more precisely what you can expect, based on your own earning history.

Two Social Security cards, resting on a bed of hundred-dollar bills.

Image source: Getty Images.

Your full retirement age

First things first -- you need to know your "full retirement age" (FRA). You may not realize it, but each of us has an age at which we can start collecting our full Social Security benefits. (Starting before or after that age will result in bigger or smaller benefit checks.) Your full retirement age is somewhere between 65 and 67, depending on when you were born:

Birth Year

Full Retirement Age

1943 to 1954

66

1955

66 and 2 months

1956

66 and 4 months

1957

66 and 6 months

1958

66 and 8 months

1959

66 and 10 months

1960 or later

67

Data source: Social Security Administration.  

Calculating your Social Security benefits

The process used by the Social Security Administration (SSA) to calculate your Social Security benefits is a bit complicated. Here's how it works: The SSA collects your earnings for every year that you worked and adjusts them for inflation. Then it takes the 35 highest-earning years and averages them, dividing by 420 (because there are 420 months in 35 years) in order to reach your "Average Indexed Monthly Earnings" (AIME). It then applies its formula to the AIME, arriving at your "Primary Insurance Amount" (PIA). That's the benefit you're entitled to at your full retirement age.

For 2018, the formula is 90% of the first $895 in your AIME (that's $805.50), 32% of the amount of AIME greater than $895, up to $5,397 (that's $1,440.64 for those with AIMEs of at least $5,397), and 15% of the amount of AIME greater than $5,397. You can see, therefore, that someone with an AIME of $5,397 would get a benefit that's the total of $805.50 and $1,440.64 -- $2,246.14. That's much more than most people will get, though, as $5,397 per month is what someone earning nearly $65,000 annually would get, and that's a higher-than-average wage. Let's move on now, to those earning that nice six-figure income.

A dial labeled benefits, pointing to maximum.

Image source: Getty Images.

What those earning $100,000 might collect from Social Security

If you earn $100,000 annually, what can you expect from Social Security? Well, there's no one-size-fits-all answer, as it will depend on how old you are now, when you start collecting your benefits, and how much you earned in each of your working years (or at least the 35 years in which you earned the most). The table below offers a rough idea, though, via an online calculator at the Social Security Administration website. Note that the benefits reflect a year of monthly benefits and that they're presented in today's dollars:

Age Today

Full Retirement Age

Start Collecting Benefits at 62

Start Collecting Benefits at FRA

Start Collecting Benefits at 70

30

67

$23,052

$33,048

$40,704

35

67

$22,836

$32,952

$40,704

40

67

$22,488

$32,640

$40,464

45

67

$22,044

$32,160

$39,996

50

67

$21,492

$31,512

$39,324

55

67

$20,856

$30,732

$38,460

60

66 and 8 months

$20,844

$32,184

$38,628

65

66

N/A

$26,376

$35,880

Data source: SSA.gov and author calculations.

How much will you get from Social Security?

Most likely, you don't earn exactly $100,000. And even if you do, the numbers above won't be as precise as they could be, as they're not based on your particular earning history. So here's how to get a good estimate of your future Social Security benefits: Start by setting up a my Social Security account with the SSA. Once you do, you'll be able to see the SSA's record of your earnings for your entire working life, as well as estimates of your future benefits. (The account will also let you correct any errors and request a replacement Social Security card (if you meet certain criteria), among other things. Setting up an account can also prevent identity theft and headaches, if you set up your account before a scammer does so for you, pretending to be you.

For context, know that the average Social Security retirement benefit was recently $1,417 per month, or about $17,000 per year. If your earnings have been above average, though, you'll get more money out of the Social Security program than most people. For 2018, the maximum benefit for those retiring at their full retirement age is $2,788 and the maximum for those who wait until age 70 is $3,698. For 2019, those numbers rise to $2,861 and $3,777, respectively.

The words want more, painted on a green background.

Image source: Getty Images.

Increase your Social Security benefits

A last key thing to know is that you have some control over how much you receive from Social Security. There are a bunch of ways to increase your Social Security benefits. For example, you might work the formula that the Social Security Administration uses to compute your benefits. It's based on your earnings in the 35 years in which you earned the most, so if you only earned income in 30 years, the formula will be incorporating five zeros, which could shrink your benefits considerably. Are you planning to retire after 32 years of work? It might be worth it to work three more years, if you want bigger benefit checks. Even if you've worked 35 years, if you're now earning much more than you have in the past (on an inflation-adjusted basis), you might consider working for another year or two, as each high-earning year will kick a low-earning year out of the calculation.

You might also delay starting to collect your benefits. The longer you delay, until age 70, the bigger your checks will be. This strategy is best for those who expect to live longer-than-average lives, though. For those with average or shorter-than-average life spans, starting as early as possible, at age 62, is generally best. After all, you may receive smaller checks, but you'll receive many more of them.

Whether you earn more or less than $100,000, Social Security is likely to provide some meaningful income to you in retirement, and it may make the difference between a comfortable retirement and a stressful one. So take some time to learn more about Social Security so that you can make smart decisions about it.

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