2018 Tax Calculation for Social Security
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Reviewed by Calculator Editorial Team
In 2018, Social Security taxes were applied to wages and self-employment income. This calculator helps you determine how much tax was withheld from your paycheck or paid on your self-employment taxes during that year.
How Social Security Taxes Worked in 2018
Social Security taxes in 2018 were based on the following rates:
- 6.2% for employees (Social Security tax)
- 6.2% for employers (Social Security tax)
- 1.45% for employees (Medicare tax)
- 1.45% for employers (Medicare tax)
The Social Security wage base in 2018 was $137,700. Any wages above this amount were not subject to Social Security taxes.
Total Social Security Tax Rate
For employees: 6.2% + 1.45% = 7.65%
For employers: 6.2% + 1.45% = 7.65%
In addition, there was a 0.9% Additional Medicare Tax on wages over $200,000 for single filers and $250,000 for married couples filing jointly.
Calculation Method
To calculate your 2018 Social Security taxes:
- Determine your total wages for the year
- Apply the 7.65% tax rate to wages up to $137,700
- Add the 0.9% Additional Medicare Tax if applicable
- Calculate the employer's share (7.65% of wages up to $137,700)
Important Notes
This calculation does not account for tax credits, deductions, or other adjustments that might affect your actual tax liability. It provides an estimate based on the standard tax rates in effect for 2018.
Worked Example
Let's calculate the Social Security taxes for a single employee earning $50,000 in 2018.
| Calculation Step | Amount |
|---|---|
| Total wages | $50,000 |
| Social Security tax (6.2%) | $50,000 × 6.2% = $3,100 |
| Medicare tax (1.45%) | $50,000 × 1.45% = $725 |
| Total employee tax | $3,100 + $725 = $3,825 |
| Employer's share (7.65%) | $50,000 × 7.65% = $3,825 |
In this example, both the employee and employer would have paid a total of $3,825 in Social Security and Medicare taxes for the year.
Frequently Asked Questions
What was the Social Security wage base in 2018?
The Social Security wage base in 2018 was $137,700. Wages above this amount were not subject to Social Security taxes.
How much did the Additional Medicare Tax add to my 2018 taxes?
The Additional Medicare Tax was 0.9% on wages over $200,000 for single filers and $250,000 for married couples filing jointly.
Did the employer pay the same amount in Social Security taxes as the employee?
Yes, both the employee and employer paid the same total amount in Social Security and Medicare taxes (7.65% of wages up to the wage base).