Try as you might to save aggressively for retirement, life's expenses might get in the way. As such, you could end up relying quite heavily on Social Security during retirement.

Even if you do manage to kick off your senior years with a healthy sum of money in your IRA or 401(k) plan, you might still want to enjoy as high a benefit as possible from Social Security. But here are a few reasons the monthly benefit you wind up collecting might ultimately come in lower than expected.

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1. You're filing before full retirement age

Your monthly Social Security benefit is calculated based on your earnings during your 35 highest-paid years in the labor force. From there, you can collect that benefit in full once you reach full retirement age, or FRA.

Many people don't know their FRA ahead of retirement and wind up claiming benefits earlier. The Social Security Administration allows seniors to file for benefits as early as age 62, and many beneficiaries sign up then to get their money as soon as possible. Meanwhile, some people claim Social Security at age 65 in conjunction with their Medicare enrollment.

But for every month you claim your benefits before reaching FRA, they'll shrink on a permanent basis. If you want to avoid that hit, you'll need to learn your FRA and wait until that age arrives to sign up for Social Security. You can consult this table to see what your FRA looks like.

Year of Birth

Full Retirement Age




66 and 2 months


66 and 4 months


66 and 6 months


66 and 8 months


66 and 10 months

1960 or later


Data source: Social Security Administration.

2. Your total retirement income is too high

If Social Security is your only retirement income source, you'll probably manage to avoid federal taxes on your benefits. But if you have other streams available to you, like retirement plan withdrawals or earnings from a part-time job, your benefits might shrink by virtue of getting taxed.

Whether that happens depends on your provisional income, which is your non-Social Security income plus 50% of your annual benefit. Once that total reaches $25,000 for singles and $32,000 for couples, taxes on benefits can apply.

One good way to avoid taxes on Social Security benefits is to house your retirement savings in a Roth IRA. Roth IRA withdrawals don't get taxed and don't count toward provisional income. If you earn too much money to fund a Roth IRA directly, you can always open a traditional IRA and then convert it to a Roth.

3. You're moving to a state that taxes benefits

Social Security income isn't just subject to federal taxes for retirees with moderate earnings. There are also 13 states that tax benefits. That list includes:

  1. Colorado
  2. Connecticut
  3. Kansas
  4. Minnesota
  5. Missouri
  6. Montana
  7. Nebraska
  8. New Mexico
  9. North Dakota
  10. Rhode Island
  11. Utah
  12. Vermont
  13. West Virginia

Obviously, steering clear of these states for retirement will help you avoid state taxes on your benefits. But keep in mind that many of the states on this list offer an exemption on taxes for low and even moderate earners.

What will your Social Security benefits look like?

The amount of money you receive from Social Security each month will hinge on a bunch of different factors. Understanding what those are is important so you can take steps to score the highest benefit possible.