Businesses need to know key tax deadlines. For organizations that handle sales tax quarterly filing due dates. Missing these state-level deadlines can be costly, with late filing and late payment penalties reaching up to 30% in some jurisdictions.

Below, we’ll discuss sales tax filing schedules, plus the income tax and estimated payment deadlines businesses often track alongside them.

Key takeaways

• While requirements vary by state, most jurisdictions mandate quarterly sales tax returns and payments by the 20th of the month following the close of the quarter.

• Unlike state sales tax, quarterly estimated federal income tax is generally due on the 15th of the following month.

• Businesses can request a six-month extension for federal tax returns. State-level sales tax extensions have entirely separate rules and must be verified with each specific department of revenue. But these extensions don’t grant extra time to pay the actual taxes owed.

Quarterly sales tax due dates

While specific deadlines vary by jurisdiction, the vast majority of states use standard calendar quarters for sales tax reporting. Returns and payments are usually due on either the 20th or the last day of the month following the close of the quarter.

A standard quarterly sales tax schedule generally looks like this:

• Q1 (January 1–March 31): Due in April (typically April 20 or April 30)

• Q2 (April 1–June 30): Due in July (typically July 20 or July 31)

• Q3 (July 1–September 30): Due in October (typically October 20 or October 31)

• Q4 (October 1–December 31): Due in January (typically January 20 or January 31)

If a tax due date falls on a weekend or recognized legal holiday, the deadline often shifts to the next business day.

Time frames vary by state, potentially requiring payments to be made monthly, quarterly, or annually. The schedule will be tied directly to your sales volume and total tax liability in your state. Consider checking with your state’s department of revenue (or taxation) to confirm it.

Generally, the more sales tax you collect, the more frequently you’ll be required to file and remit those funds. Conversely, smaller businesses with minimal tax obligations might be able to file annually. It’s important to check with your state’s tax authority to confirm your exact assigned frequency, as well as its specific due dates.

State-by-state sales tax due dates

Here’s how sales tax due dates differ across several states.

What happens if you miss a due date?

Missing a sales tax deadline triggers immediate financial and operational consequences. Because states rely heavily on sales tax revenue, they enforce strict compliance through several mechanisms:

• Penalties and interest: Most states assess both a late filing penalty for missing the return deadline and a late payment penalty. These are a percentage of the unpaid tax, which can range anywhere from 5%–30% depending on the state. Statutory interest also accrues monthly on the unpaid balance until it’s resolved.

• Loss of vendor discounts: Nearly 30 states offer a vendor discount (or timely filing discount) that allows businesses to keep a small percentage of the sales tax they collect as compensation for administering the tax. If you miss the filing or payment deadline, you’ll immediately forfeit this discount.

• Audit risk and permit revocation: Consistently filing late or failing to remit tax is a massive warning sign for state tax authorities. It significantly increases your likelihood of being audited. Sustained noncompliance can lead to the state placing tax liens on your business or revoking your sales tax permit entirely.

Income tax due dates

For small businesses, tracking income tax due dates is just as important as tracking sales tax due dates. The US Internal Revenue Service (IRS) imposes penalties of up to 25% of the unpaid amounts for businesses that fail to pay their taxes on time.

Here are the typical deadlines for businesses to pay income tax:

• C corporations (C corps): The income tax return (Form 1120) is due on April 15 for C corps that follow the calendar year. For corporations that operate on a fiscal year, amounts are due on the 15th day of the third month after that cycle ends.

• S corporations (S corps) and partnerships: These business structures must file their returns by the 15th day of the third month after the tax year ends, whether it’s a calendar year or fiscal year. S corps use Form 1120-S, and partnerships use Form 1065.

• Sole proprietorships: Sole proprietors report their business earnings on their tax returns (Form 1040), due April 15. They use Schedule C to report profit or loss from the operation.

Estimated tax payments

Estimated tax payments are quarterly amounts that individuals and businesses give the IRS throughout the year to cover their expected tax liabilities. These payments are required for sole proprietors, partners, and S corp shareholders if they expect to owe $1,000 or more when they file their returns. The same applies to C corps that expect to owe at least $500.

Who needs to make estimated tax payments?

• Self-employed individuals: If you earn income from self-employment (e.g., freelancing, consulting, running a business), you’ll often be required to make estimated tax payments.

• Investors: If you earn substantial earnings from investments such as dividends, interest, and capital gains, you might need to make projected payments.

• Employees with side income: If you have a regular job with withholdings, you might need to make estimated payments if you earn substantial additional revenue.

When are estimated tax payments due?

These are the due dates for estimated tax payments:

• Q1 (January 1–March 31) payments are due by April 15.

• Q2 (April 1–May 31) payments are due by June 15.

• Q3 (June 1–August 31) payments are due by September 15.

• Q4 (September 1–December 31) payments are due by January 15 of the following year.

How to calculate estimated tax payments

Here are the steps to calculating estimated tax:

• Estimate your income: Determine your expected income for the year, including all sources of revenue.

• Calculate your tax liability: Use the current tax rates and deductions to approximate your total liability for the year.

• Subtract withholding: If amounts are withheld from your paycheck or other sources, subtract them from your projected total.

• Divide by four: Divide the remaining figure by four to determine your quarterly estimated tax payment.

How to make estimated tax payments

You can make these payments online, by mail, or by phone using the Electronic Federal Tax Payment System. You can also use IRS Direct Pay or pay through your online IRS account.

Extension deadlines

Businesses can usually apply for extensions when they file their federal or state tax returns. Here’s what to know:

• Federal tax returns: Businesses can request a six-month extension for their federal tax returns. They must do so by the original due date. The forms differ by entity type. C corps, S corps, and partnerships use Form 7004, while sole proprietorships use Form 4868.

• State tax returns: Extension deadlines and procedures vary, so it’s important to consult your state’s department of revenue for specific information. In many cases, states will automatically grant a state filing extension if you’ve already successfully filed for a federal extension, but some still require a separate state-level application.

• Sales tax returns: Check with your state’s department of revenue for any extension rules regarding these filings. The most common exception is a state-issued blanket extension automatically granted to businesses in areas affected by a declared natural disaster. It’s important to note that even if an extension is granted, it’s almost exclusively an extension to file. You must still estimate and remit your tax liability by the original due date to avoid accruing statutory interest and late payment penalties.

How Stripe Tax can help

Stripe Tax reduces the complexity of tax compliance so you can focus on growing your business. Start collecting taxes globally by adding a single line of code to your existing integration, clicking a button in the Dashboard, or using our powerful application programming interface (API).

Stripe Tax helps you monitor your obligations and alerts you when you exceed a tax registration threshold based on your Stripe transactions. It can also register to collect tax on your behalf in the US, automate US filings in the Dashboard, and manage global filings through trusted partners. Stripe Tax automatically calculates and collects sales tax, value-added tax (VAT), and goods and services tax (GST) on:

• Digital goods and services in all US states and over 100 countries

• Physical goods in all US states and 42 countries

Stripe Tax can help you:

• Understand where to register and collect taxes: See where you need to collect taxes based on your Stripe transactions. After you register, switch on tax collection in a new state or country in seconds. You can start collecting taxes by adding one line of code to your existing Stripe integration, or add tax collection with the click of a button in the Stripe Dashboard.

• Register to pay tax: If you need to register for a sales tax in the US, let Stripe manage your tax registrations. You’ll benefit from a simplified process that prefills application details—saving you time and simplifying compliance with local regulations. If you need help registering outside of the US, Stripe partners with Taxually to help you register with local tax authorities.

• Automatically collect tax: Stripe Tax calculates and collects the right amount of tax owed, no matter what or where you sell. It supports hundreds of products and services and is up-to-date on tax rules and rate changes.

• Simplify filing: Stripe Tax automates US filings in the Dashboard, powered by TaxJar. For global filings, Stripe Tax seamlessly integrates with filing partners, so your global filings are accurate and timely. Let our partners manage your filings so you can focus on growing your business.

Learn more about Stripe Tax, or get started today.