Most years, the government bumps up the maximum Social Security taxes that you can pay.  For 2021, the maximum wage base jumps to $142,800, an increase of $5,100, or 3.7%, over the max of $137,700 that was in place for 2020.

At a rate of 6.2%, the maximum Social Security taxes that your employer will withhold from your salary is $8,854. This is $317 higher than the 2020 max of $8,537.

How is this increase calculated? According to the Social Security Administration, the annual change is based on the National Wage Index.

Higher Medicare Taxes Due To The Affordable Care Act:

Starting back in 2013, the employee portion of the Medicare tax jumps from the current rate of 1.45% to 2.35% on earned income in excess of $200k for single individuals and $250k for married couples filing a joint tax return. As of now, the employer will continue to match their employees’ Medicare taxes at a rate of 1.45%, which means the total Medicare tax will be 3.8% for high-income taxpayers. This tax is reported on the Form 8959.

For example, if you’re single, and earn $500k from your job, expect to pay $2,700 in additional Medicare taxes (($500k – $200k) * .9%) for 2013 and beyond.

To increase taxes for high-income individuals even more, the Medicare tax will also apply to unearned income for the first time since this tax was enacted. People over the $200k or $250k threshold should expect to pay Medicare taxes at a rate of 3.8% on interest, dividends, capital gains, and net rental income (except for when you rent office space you own to your practice) beginning in 2013. You will pay this tax in addition to any federal and state income taxes due on this income. This tax is reported on the Form 8960.

Calculating the Self-employment Tax:

If you’re self-employed and earn more than $400 in net profit from your business, you’re subject to social security and Medicare taxes as well. Known as the “self-employment tax”, you’ll need to complete a Schedule SE to calculate this tax, and then report the amount due on your Form 1040.

The self-employment tax is based on a social security tax rate of 12.4% and a Medicare tax rate of 2.9%. These rates are double those paid by employees, since a self-employed person must pay both the employee’s portion and the employer’s portion of both taxes. Remember, when you work as an employee, your employer matches the Social Security and Medicare taxes withheld from your pay.

Unlike most other taxes, when dealing with self-employment taxes, the more you earn, the less you pay in taxes. If you earn income as an employee and as an independent contractor, and your combined income exceeds $137,700 in 2020, make sure to complete Section B of the Schedule SE. Otherwise, your tax calculation will be incorrect and you’ll end up overpaying your self-employment taxes.

Do You Work For More Than One Employer in 2020 and Earn More Than $137,700?

For 2020, each of your employers withholds social security taxes from the first $137,700 that you earn from them. If you work for more than one employer and your total salary from all sources exceeds that threshold, you’ll have excess social security taxes withheld. Make sure to claim a credit for these excess taxes on your 1040 as additional federal taxes paid in.

For Example:

Let’s say you work for two employers and earn $100,000 from each employer. Employer #1 withholds $6,200 in social security taxes ($100,000 * 6.2%). Employer #2 also withholds $6,200 in social security taxes – for a total of $12,400 in social security taxes withheld during the year. Since the maximum social security taxes that you should pay through payroll withholdings for 2020 is limited to $8,537, the excess of $3,863 counts as additional federal income taxes paid in by you.