When are 2018 Tax Returns Due? Every Date You Need to File Business Taxes in 2019

Filing and paying your taxes on time is a lot easier when you a) know when they’re due (obviously) and b) have a year-round accounting system. When you outsource your business’s accounting and taxes with indinero, we have you covered on both fronts, but, in this article, we’ll focus on the former to help all business owners build a 2018 business tax calendar so they can keep up with their filing responsibilities and avoid late penalties.

(Still working on your 2018 business taxes? You can find those dates in the 2017-2018 version of this calendar.)

Do you use an Alternative Fiscal Year? Read this:

For the purpose of this article, we’ve used the calendar year (January 1 through December 31). If your business uses another fiscal year, click here to jump down and see how to adjust your tax calendar accordingly.

When are 2018 business taxes due in 2019?

Using your entity type, you can identify what your deadline is for filing business taxes and what it would be if you elect to take advantage of the extension, but you’ll also need to take weekends and federal holidays into account.

The following table covers when each type of business entity needs to file 2018 taxes in 2019 (using the calendar year):

2019 Tax Deadlines for Filing 2018 Business Returns

Partnership Tax Deadlines: Due Date:
Original tax deadline for partnerships (Form 1065) March 15, 2019
Extension tax deadline for partnerships (Form 1065) September 16, 2019
S Corporation Tax Deadlines: Due Date:
Original tax deadline for S Corporations (Form 1120S) March 15, 2019
Extension tax deadline for S Corporations (Form 1120S) September 16, 2019
C Corporation Tax Deadlines: Due Date:
Original tax deadline for C Corporations (Form 1120) April 15, 2019
Extension tax deadline for C Corporations (Form 1120) October 15, 2019
Sole Proprietor Tax Deadlines: Due Date:
Original tax deadline for sole proprietors and individuals (Form 1040) April 15, 2019
Extension tax deadline for sole proprietors and individuals (Form 1040) October 15, 2019
Nonprofit Tax Deadlines: Due Date:
Original tax deadline for exempt organizations (Form 990) May 15, 2019
Extension tax deadline for exempt organizations (Form 990) August 15, 2019

What Flow-Through Entities (S Corps or Partnerships) Need to Do By Their Tax Deadline

If your business is a flow-through entity—S Corporation or partnership (LLC)—your taxes are due on the fifteenth day of the third month of your fiscal year or the fifteenth day of the ninth month if you file an extension. However, those entities get the name “flow-through” or “pass-through” because they do not pay income tax.

As a flow-through, your business’s income and losses get passed on to the partners, owners, and shareholders. So when your flow-through entity files a Form 1065 to the IRS, you must also issue Schedule K-1s to each partner or shareholder for them to report on their individual returns. For this reason, if you plan on electing to extend your tax deadline, be sure and let all partners and shareholders know so they can do the same!

What Individuals and C Corps Need to Do By Their Tax Deadline

As an individual (including sole proprietors) or corporation, your taxes are due on the fifteenth day of the fourth month of your fiscal year or the fifteenth day of the tenth month if you file an extension. This means you will file your taxes or an extension on April 15, 2019, and pay any tax liability you owe. If you ask for an extension, you will file taxes by October 15, 2019, but you will still need to pay taxes by April 15.

What Exempt Organizations (Nonprofits and Charities) Need to Do By Their Tax Deadline

As an exempt organization, such as a nonprofit or charity, you will file taxes on the fifteenth day of the fifth month of your fiscal year or the fifteenth day of the eighth month if you file an extension. For your 2018 return, you will need to file your taxes or an extension by May 15, 2019. If you ask for an extension, you will have until August 15, 2019 to file your return.

Give Yourself Time to Adapt to Tax Code Changes

One thing we can’t stress enough about business taxes is how crucial it is to give yourself time to prepare. At the very minimum, take a few hours at the end of the year to get things in order before you close your books in January, but more ideally you should be working with an accounting professional to plan for the tax implications of your business’ spending and earnings throughout the year. (Read this article to understand what time of year you should to start working with an accountant.)

Experts are still interpreting the Tax Cuts and Jobs Act that went into effect on January 1, 2018, but they are already seeing some ways the new code will limit businesses’ ability to minimize their tax liability. One example is the stricter limits on deducting expenses for meals and entertainment. For this reason, avoiding procrastination on taxes now more crucial than ever. Waiting until the last minute to start preparing is never a good idea, but, with so much still to be determined this year, it’s best to work with a tax professional ASAP to avoid surprises when you go to file.

Need extra time to get organized? Consider the tax extension for your 2018 business taxes:

Maybe you had a busy last few months of the year, something disruptive from your personal life took priority, or your 2018 business activities had way more tax consequences than you expected. If you reach a point and think there’s no way you’ll be able to gather everything you and your CPA need to file your taxes by your original deadline, then please extend!

C Corporations, Partnerships, and S Corporations use Form 7004 to request a 6-month extension; individuals use Form 4868. Nonprofits can request a 3-month extension using Form 8868.

But first, talk about it with your tax preparer. There may be a reason they haven’t brought it up yet. Moreover, remember that an extension only applies to your deadline for filing your return, NOT paying the taxes you’ll owe (more about that here).

When are 2018 estimated quarterly tax payments due for profitable businesses?

If your business is profitable, you will be responsible for paying tax on your income in quarterly installments throughout the year. These are due by the fifteenth day of the fourth, sixth, ninth, and twelfth* months of the year (see IRS Form 1120-W). If you miss your estimated tax payments, you can always pay them in full when you go to file at the end of the year, but expect also to pay interest and penalties on what you owe.

2018 Estimated Tax Payment Due Dates (Calendar Year):

Quarterly Deadline: Due Date:
First Quarter Tax Estimate Deadline April 17, 2018
Second Quarter Tax Estimate Deadline June 15, 2018
Third Quarter Tax Estimate Deadline September 17, 2018
Fourth Quarter Tax Estimate Deadline (Corporations) December 17, 2018
Fourth Quarter Tax Estimate Deadline (Individuals) January 15, 2019

Other Things to Consider When Filing Your 2018 Taxes:

If your business has any foreign relationships or activities during 2018…

Missing a filing deadline gets much more expensive if you have business relationships overseas. For example, if you have a U.S. partnership with foreign shareholders (non-U.S. citizens or residents) who own more than 25%, you are required to file Form 5472 with you partnership’s return. If you fail to file a complete and correct 5472 for all of your foreign shareholders who fit that description, you can expect a $10,000 penalty per required shareholder per month. (This guide breaks down the various foreign tax filing responsibilities and the penalties for failing to meet your requirements.)

If you start or stop your business during 2018…

It might be tempting to forget about taxes in the first and last year of your business, but in both cases, the entity will still need to file under a short year return. Similarly, some seasonal businesses that only exist for portions of each year will also file a short year return.

If you start a business in 2018, you will need to file taxes starting from the date of incorporation through the end of the year. The costs you incurred before you started your business won’t be deductible, but by working with a tax expert, you may find you’re able to capitalize and deduct those costs over the next 15 years.

If you shut down your business in 2018, you’ll want to record the exact date you close your doors for tax purposes. You will need to file a return that includes all income and expenses up to the dissolution date. All that should be left in any business accounts after the business is over are the amounts that you plan to distribute to investors as you cash out and the amount you reserve for paying any final tax liability.

If you convert your LLC into a C Corp in 2018…

Anytime a business converts from an LLC to a C Corporation, it’s crucial that tax and legal professionals get involved. As we’ve covered in the past, transitioning your business from LLC to C-Corp can come with costly tax penalties if the partners fail to file a short tax year return and pay their income tax liability within three months. After three months each partner will owe $195 per each month the return is late.

If you receive a notice from the IRS or a state tax authority in 2018…

All federal or state tax notices will have a deadline by when the taxpayer must respond. Be sure to respond promptly and consult a tax professional about how you should proceed. But also, don’t freak out! If you get a notice from a tax authority—whether for a correction or an actual audit—follow these instructions and tips for working with the IRS.

Build Your Own 2018-2019 Business Tax Return Calendar

Add the relevant dates to your 2018-2019 calendar to stay on top of your business taxes:

Profitable? Add the 2018 Estimated Quarterly Payment Deadlines to your calendar:

  • Q1: April 17, 2018
  • Q2: June 15, 2018
  • Q3: September 17, 2018
  • Q4: December 17, 2018 (Corporations)
  • Q4: January 15, 2019 (Individuals)

Partnerships and S Corporations should add these 2019 filing deadlines for flow/pass-through entities to their calendars:

  • Regular: March 15, 2019
  • Extended: September 16, 2019

Individuals and C Corporations should add these 2019 filing deadlines to their calendars:

  • Regular: April 15, 2019
  • Extended: October 15, 2019

Nonprofits and charities should add these 2019 filing deadlines for exempt organizations to their calendars:

  • Regular: May 15, 2019
  • Extended: August 15, 2019

If applicable, add these to your 2018-2019 dates to your tax calendar:

  • Last day to pay employee bonuses that qualify toward 2018 business taxes: February 15, 2018
  • #GivingTuesday 2018: November 27, 2018
  • The date you start doing business in 2018
  • The date you stop doing business in 2018
  • Deadlines for any notices from the state/IRS you receive in 2018

Start Planning Now to Save As Much As Your Can on 2018 Taxes

As a small business, there are many ways to save on taxes, but each takes a certain degree of planning ahead. Knowing your key tax deadlines is a huge step toward being compliant and avoiding late fees and penalties.  Learn more about how indinero can help you build a comprehensive strategy.

Rethink your tax prep with indinero

*Recalculating Your 2018-2019 Tax Calendar for an Alternative Fiscal Year:

If you use a fiscal year instead of the calendar year for your business taxes, you’ll still file taxes in the same cadence (i.e. the 15th day of the third, fourth, or fifth month), but you may need to crunch some numbers to determine your actual tax deadlines. Follow the chart below to see when your taxes are due based on the day your fiscal year ends:

Use this chart to calculate your 2018-2019 tax year calendar based on your fiscal year end

Quick Note: This article is provided for informational purposes only, and is not legal, financial, accounting, or tax advice. You should consult appropriate professionals for advice on your specific situation. indinero assumes no liability for actions taken in reliance upon the information contained herein.