retirement

Working for yourself, either as a part-time side hustle or a full-time endeavor, can be very exciting and financially rewarding. But one downside to self-employment is that you're responsible for following special tax rules. Missing tax deadlines or paying the wrong amount can lead to expensive penalties.

Let's talk about what the self-employment or SE tax is and how it compares to payroll taxes for employees. You’ll learn who must pay the SE tax, how to pay it, and tips to stay compliant when you work for yourself.

What is the self-employment (SE) tax?

In addition to federal and applicable state income taxes, everyone must pay Social Security and Medicare taxes. These two social programs provide you with retirement benefits, disability benefits, survivor benefits, and Medicare health insurance benefits.

Many people don’t realize that when you’re a W-2 employee, your employer must pick up the tab for a portion of your taxes. Thanks to the Federal Insurance Contributions Act (FICA), employers are generally required to withhold Social Security and Medicare taxes from your paycheck and match the tax amounts you owe.

In other words, your employer pays half of your Social Security and Medicare taxes, and you pay the remaining half. Employees pay 100% of federal and state income taxes, which also get withheld from your wages and sent to the government.

When you have your own business, you’re typically responsible for paying the full amount of income taxes, including 100% of your Social Security and Medicare taxes.

But when you have your own business, you’re typically responsible for paying the full amount of income taxes, including 100% of your Social Security and Medicare taxes.

Who must pay the self-employment tax?

All business owners with "pass-through" income must pay the SE tax. That typically includes every business entity except C corporations (or LLCs that elect to get taxed as a corporation).

When you have a C corp or get taxed as a corporation, you work as an employee of your business. You're required to withhold all employment taxes (federal, state, Social Security, and Medicare) from your salary or wages. Other business entities allow income to pass directly to the owner(s), so it gets included in their personal tax returns.

You must pay the SE tax no matter if you call yourself a solopreneur, independent contractor, or freelancer—even if you're already receiving Social Security or Medicare benefits.

You must pay the SE tax no matter if you call yourself a solopreneur, independent contractor, or freelancer—even if you're already receiving Social Security or Medicare benefits.

How much is the self-employment tax?

For 2020, the SE tax rate is 15.3% of earnings from your business. That's a combined Social Security tax rate of 12.4 % and a Medicare tax rate of 2.9%.

For Social Security tax, you pay it on up to a maximum wage base of $137,700. You don't have to pay Social Security tax on any additional income above this threshold. However, this threshold has been increasing and is likely to continue creeping up in future years.

However, for Medicare, there is no wage base. All your income is subject to the 2.9% Medicare tax.

So, if you're self-employed with net income less than $137,700, you'd pay SE tax of 15.3% (12.4% Social Security plus 2.9% Medicare tax), plus ordinary income tax.

Remember that your future Social Security benefits get reduced if you don't claim all of your self-employment income.

What is the additional Medicare tax?

If you have a high income, you must pay an extra tax of 0.9%, known as the additional Medicare tax. This surtax went into effect in 2013 with the passage of the Affordable Care Act (ACA). It applies to wages and self-employment income over these amounts by tax filing status for 2020:

• Single: $200,000 
• Married filing jointly: $250,000 
• Married filing separately: $125,000 
• Head of household: $200,000 
• Qualifying widow(er): $200,000

What are estimated taxes?

As I mentioned, when you’re an employee, your employer withholds money for various taxes from your paychecks and sends it to the government on your behalf. This pay-as-you-go system was created to make sure you pay all taxes owed by the end of the year.

You must make quarterly estimated tax payments if you expect to owe at least $1,000 in taxes, including the SE tax.

When you’re self-employed, you also have to keep up with taxes throughout the year. You must make quarterly estimated tax payments if you expect to owe at least $1,000 in taxes, including the SE tax.

Each payment should be one-fourth of the total you expect to owe. Estimated payments are generally due on:

• April 15 (for the first quarter) 
• June 15 (for the second quarter) 
• September 15 (for the third quarter) 
• January 15 (for the fourth quarter) of the following year

But when the due date falls on a weekend or holiday, it shifts to the next business day. Your state may also require estimated tax payments and may have different deadlines.

How to calculate estimated taxes

Figuring estimated payments can be extremely confusing when you’re self-employed because many entrepreneurs don’t have the faintest idea how much they’ll make from one week to the next, much less how much tax they can expect to pay. Nonetheless, you must make your best guesstimate.

If you earn more than you estimated, you can pay more on any remaining quarterly tax payments. If you earn less, you can reduce them or apply any overpayments to next year’s estimated payments.

If you (or your spouse, if you file taxes jointly) have a W-2 job in addition to self-employment income, you can increase your tax withholding from earnings at your job instead of making estimated payments. To do this, you or your spouse must file an updated Form W-4 with your employer.

The IRS has a Tax Withholding Estimator to help you calculate the right amount to withhold from your pay for your individual or joint taxes.

How to pay estimated taxes

To figure and pay your estimated taxes, use Form 1040-ES, Estimated Tax for Individuals, or Form 1120-W, Estimated Tax for Corporations. These forms contain blank vouchers you can use to mail in your payments, or you can submit funds electronically.

When you have a complicated situation, including having business income, one of your new best friends should be a tax accountant.

For much more information about running a small business successfully, check out my newest book, Money-Smart Solopreneur: A Personal Finance System for Freelancers, Entrepreneurs, and Side-Hustlers. Part four, Understanding Business Taxes, covers everything you need to know to comply and stay out of trouble.

From personal experience, I can tell you that when you have a complicated situation, including having business income, one of your new best friends should be a tax accountant. Find one who listens well and seems to understand the kind of work you're doing.

A good accountant will help you calculate your estimated quarterly taxes, claim tax deductions, and save you money by helping you take advantage of every tax benefit that's allowed when you're self-employed. In Money-Smart Solopreneur, I recommend various software, online services, and apps to help you track expenses, deductions, and tax deadlines that will keep your business running smoothly.