Newly Self-Employed? Don’t Miss the September 15 Estimated Tax Deadline

If you recently started working for yourself in 2025 — whether by choice or after a layoff — congratulations on taking the leap! But here’s something many new business owners don’t realize: when you’re self-employed, no one withholds taxes from your paycheck. That means you’re responsible for paying self-employment (SE) tax and income tax directly to the IRS.

And instead of paying once a year in April, you often have to pay quarterly estimated taxes.

What Is Self-Employment Tax?

When you worked for an employer, they withheld Social Security and Medicare taxes from your paycheck, and they paid the other half for you. Now that you’re self-employed, you pay both halves yourself through SE tax. It’s about 15.3% of your net business income, on top of regular income tax.

This surprises a lot of new entrepreneurs — but planning for it will save you stress later.

Why Quarterly Estimated Taxes Matter

The IRS expects you to pay as you go, not all at once in April. If you don’t send in estimated payments, you could face penalties, even if you pay in full at tax time.

Estimated payments cover both:

• Income tax (based on your profit)

• Self-employment tax (Social Security + Medicare)

  
  

Quarterly Deadlines Aren’t All Equal

Here’s where it gets tricky: the IRS “quarters” don’t line up neatly with calendar quarters.

Payment Covers Income Earned In	Payment Due Date
January 1 – March 31	April 15
April 1 – May 31	June 15
June 1 – August 31	September 15
September 1 – December 31	January 15 (following year)

That means the September 15 payment is coming up soon, and it covers your income from June, July, and August 2025.

How Much Should You Pay?

There are two common approaches:

• Safe harbor: Pay the same amount each quarter, based on last year’s tax liability.

• Current year method: Base it on your actual profit so far this year (more accurate if your income has changed).

You can make your payment online here: IRS Direct Pay. Don't forget - your state may also require quarterly estimated payments.

New to Self-Employment? You’re Not Alone

Many people who’ve started freelancing, consulting, or running a small business after layoffs this year are facing estimated taxes for the very first time. It can feel overwhelming — but getting in the habit now will set you up for success and help you avoid year-end surprises.

Next Steps

• Mark your calendar: The next estimated tax payment deadline is September 15.

• Run your numbers: Estimate your profit from June through August and set aside the right amount for taxes.

• Explore resources: Check out our free Small Business Resources to help you stay organized and tax-ready.

• Get support if needed: At Be Well & Co. Financial Consulting, we offer a Self-Employed Support Package to take the guesswork out of quarterly payments and give you peace of mind.

Book a Discovery Call

This reminder is provided for educational purposes only and does not constitute financial, legal, or tax advice. Please consult with a qualified professional about your specific situation.

Written by Courtney Mallow, IRS-Registered Tax Preparer, Certified Fraud Examiner (CFE), Certified Personal Financial Wellness Consultant℠, and Founder of Be Well & Co. Financial Consulting. Courtney helps self-employed individuals, people living abroad, and global professionals align their money with their values.