How to Plan for and Minimize the Self-Employment Tax

The Self-Employment Tax—What It Is and How to Pay Less

A craftsman in his workshop holding a violin.

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The self-employment tax has an ominous and discouraging ring to it, and to some extent that's fair. It's how an independent contractor pays her Social Security and Medicare taxes.

All workers have to pay Social Security and Medicare, but in the case of an employee, he and his employer would split the cost. They would each pay 7.65 percent of eligible wages. But an independent contractor is both the employer and the employee so a self-employed person must pay both halves—or 15.3 percent total. This is referred to as the self-employment tax.

How It Breaks Down

The 15.3 percent self-employment tax is composed of a 12.4 percent Social Security tax on the first $128,400 of net self-employment income for the year 2018 and a Medicare tax of 2.9 percent on all net self-employment income.

The $128,400 ceiling is called the "Social Security wage base." It represents the maximum amount of income from wages and net self-employment income that's subject to the Social Security tax. This base increases a little each year to adjust for inflation.

What Is Net Self-Employment Income?

Net self-employment income consists of income from self-employed business activities (Schedule C), farming (Schedule F), the self-employed earnings of a partner (Schedule E), and clergy and employees of churches and religious organizations. It's income after deducting business expenses, such as furniture, building repairs and purchased inventory.

Calculating Self-Employment Tax

You would next adjust your net self-employment by multiplying it by 92.35 percent. This 92.35 percent factor takes into account that part of the Social Security and Medicare taxes are a deductible business expense for employers. So self-employed taxpayers are permitted to deduct the employer’s portion of Social Security and Medicare taxes—7.65 percent—on their own tax returns.

When you subtract this 7.65 percent from 100 percent, it comes out to 92.35 percent.

This reduction in the base amount of income that's subject to the self-employment tax along with the above-the-line deduction available to self-employed taxpayers for the employer portion of the tax helps equalize the tax treatment between self-employed persons and employees.

Increase Your Business Expenses

The only surefire way to reduce your self-employment tax is to increase your business-related expenses. This will reduce your net income and correspondingly reduce your self-employment tax. Regular deductions such as the standard deduction or itemized deductions won't reduce your self-employment tax.

Above-the-line deductions for health insurance, SEP-IRA contributions, or solo 401(k) contributions will not reduce your self-employment tax, either. These deductions only reduce the federal income tax.

You might want to consider one tactic when you're preparing your tax return—the impact of taking the Section 179 deduction or bonus depreciation for fixed assets. This will impact both your income tax and the self-employment tax so you might want to speak with a tax professional to find out if you qualify.

Increase the Self-Employment Tax During Years With Losses

It sometimes happens that a taxpayer actually wants to increase his self-employment tax in order to maintain eligibility for Social Security retirement or disability benefits. In general, people need at least 40 Social Security credits over their lifetimes to be eligible for retirement benefits and at least five years of credits out of 10 to be eligible for disability benefits.

Self-employed people who are facing a year in which they have lost money—their expenses were greater than their incomes—or a year in which their incomes are significantly lower can use a special method to increase their self-employment tax. This is called the "Optional Method" and the rules are spelled out in the ​Instructions for Schedule SE.

Self-employed persons who are not farmers or fisherman are limited to using this optional method only five times in their lifetimes.

Consider Forming an S-Corporation

This might seem a little extreme but it should save you some tax dollars if you do it right. The self-employment tax applies specifically to earned income. If your clients or customers pay your S-corp, not you directly, that's not earned income to you...yet.

But you need to pay your personal bills, right? You need earned income.

So divvy up those payments and pay yourself a percentage of them as a salary and the balance as dividends. The "salary" portion is earned income and is therefore subject to self-employment tax. But dividends aren't subject to self-employment tax so you've reduced your net self-employment income by whatever percentage you took as dividends.

This can be admittedly tricky so you might want to enlist the help of a tax professional to get it right.