If you are like most people, once you have your W-2 and other tax or financial information you bring it a CPA or other qualified tax professional, and let them handle the rest. You may or may not get a tax refund, but at least you know that your taxes are paid, and that you are not on the hook for any additional funds to the IRS. If you are self-employed, however, or run your own business in addition to having a 9-5 elsewhere, you might have been forgetting one important aspect of entrepreneurship -- self-employment taxes.

Like any business, however, if your business is turning a profit the IRS will expect you to pay taxes on these profits, and there are consequences for not filing these taxes. Basically, the idea is to replicate what you happen if you had a 9-5 job, and your employer was withholding taxes on your behalf throughout the year. When you own your own business, or even have a side hustle that is producing a nice little profit, you have to step into the shoes of the employer, and pay estimated income taxes throughout the year. If this sounds a little scary, don't worry, the IRS actually has an entire page dedicated to helping you understand what quarterly taxes are, and how to file them.

This quarter's deadline to pay up is June 15, 2017, so let's take a look at some of the most common questions my fellow CPAs and I hear regarding quarterly taxes.

1. Do I have to pay quarterly taxes?

First things first, you have to determine whether or not your business earned a profit for the tax year in question. This is done by subtracting business expenses from business revenues - if your net earnings from self-employment were over $400 you should file an income tax return for this business. If your business generated a loss, however, you can generally deduct this loss from your income on your personal 1040.

2. Am I in the clear if I get a 1099 for my side business?

This is a common pitfall among consultants and entrepreneurs who establish a side business and receive a Form 1099. Although you may be receiving regular paychecks from your employer, as a 1099 employee you are self-employed and are responsible for paying your estimated taxes if necessary. The 1099 really just lets the IRS know where you are receiving income for the tax year in question - the filing of estimated tax payments is up to you.

3. How much will I actually owe?

This can get a little complicated, but basically comes down to how much self-employment income you have actually earned. Self-employment income up to $118,500 is subject to a tax rate of 15.3 percent, and amounts over this amount are subject to an additional 2.9 percent tax., or a total tax rate of 18.2 percent. This may sound a little odd, but represents both the employer and employee portions of Social Security and Medicare taxes. You can see some more detail below.

4. What if I make a mistake in one of my estimated payments?

If you underpay in one quarter, make sure to make up the payment in the next quarter, and if you overpay for the entire year you can apply it to next year's quarterly tax payments.

5. Can I see some numbers of how estimated payments might work?

Every individual and business will be different, and it's important to consult with your tax professional, but generally speaking the process will work as follows. For example, if your projected self-employment income is $8,000 for the current year, you have to make estimated payments worth 90% of this income. Since these payments are due quarterly, the total estimated tax is ($8,000 x .90), or $7,200. Divide that into four quarterly payments of $1,800 and submit the payment to the IRS along with form 1040-ES. Conversely, you can base your estimate for quarterly taxes on your most recent self-employment income from the most recent tax year.

Obviously, every business is different, and your state may have additional filing requirements for small business owners on top of these guidelines. Form EZ 1040-ES provides you some guidance, in a worksheet format, to determine how much (if any) quarterly taxes you may owe, so there are resources out there to help. Running your own business, or trying to scale a side hustle is hard enough, and forgetting about quarterly taxes can cost you big time, so taking a little time to prepare is well worth the investment.

Published on: May 30, 2017
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