You’re making money on your own now: freelancing, running a business, pulling in investment income. Great. But there’s no employer taking taxes out of your check. The IRS has a rule: you have to pay your taxes as you earn the money, not just in one lump sum every April. If you don’t, they charge you a penalty for being late. It’s called the “underpayment penalty,” and it’s a totally avoidable waste of money.
Making estimated quarterly tax payments is how you follow that “pay-as-you-go” rule. You’re sending the IRS money four times a year so you don’t get hit with a surprise bill and penalties next April.
Who This Applies To
You have to do this if you expect to owe at least $1,000 in tax for the year, after subtracting any tax that’s already being withheld (like from a W-2 job).
This isn’t just for people with businesses. This includes:
- Freelancers, consultants, gig workers (Uber, DoorDash, Upwork).
- Sole proprietors (Schedule C filers).
- Partners in a business (you get a K-1).
- S-Corp owners who take distributions beyond a reasonable salary.
- Anyone with a lot of investment income (dividends, interest, capital gains) that isn’t subject to withholding.
- Retirees with significant IRA distributions or rental income.
If you also have a regular job, you might be able to skip the quarterly payments by dramatically increasing the tax withheld from your paycheck using a new Form W-4. This is often the easiest fix.
The Deadlines
The IRS year is split into four uneven payment periods. Mark these dates:
- April 15: For income you made January 1 through March 31.
- June 15: For income April 1 through May 31 (note: this “quarter” is only 2 months long).
- September 15: For income June 1 through August 31.
- January 15 (of the next year): For income September 1 through December 31.
Important: If the 15th is a weekend or federal holiday, the deadline moves to the next business day.
You don’t need to be a psychic and guess your exact income. The IRS gives you a safe harbor to avoid the penalty. To be penalty-free, your total payments for the year (withholding + estimated payments) must equal the smaller of:
- 90% of the tax you’ll owe for this current year, OR
- 100% of the total tax you owed last year (use your prior-year Form 1040, Line 24).
- If your prior-year Adjusted Gross Income (AGI) was over $150,000 ($75,000 if Married Filing Separately), you must pay 110% of last year’s tax.
The “100% of Last Year’s Tax” Rule is Your Safety Net.
This is the most useful rule. Example: Last year, your total tax was $10,000. This year, your business booms and you’ll actually owe $30,000. As long as you pay in at least $10,000 (or $11,000 if your AGI was high) via withholding and estimated payments during the year, you will owe ZERO penalty, even though you’ll still have to pay the remaining $20,000 when you file your return.
This is why your first year in business often has no penalty—if you owed little tax last year, your safe harbor amount is very low.
The Mechanics
- Form 1040-ES: This is for individuals. The package includes a worksheet to help you estimate your income and tax. You don’t file this form; you just use it to figure out your payment amount. Then you make the payment separately.
- Form 1120-W: This is for Corporations (C-Corps and S-Corps) to calculate their estimated tax.
How to Actually Send the Money (It’s Simple):
- IRS Direct Pay (Easiest & Free): Go to IRS.gov/DirectPay. You can pay directly from your checking or savings account. Select “Estimated Tax” as the reason.
- EFTPS (Electronic Federal Tax Payment System): The official system. You need to enroll.
- Credit/Debit Card: Through an IRS-approved processor. They charge a convenience fee (about 1.9% – 2.3%).
- Check with Payment Voucher: Mail a check with the voucher from Form 1040-ES. This is the slowest method and not recommended.
You’ll get a bill from the IRS for the Underpayment of Estimated Tax Penalty. It’s not a fixed fine; it’s calculated like interest for the time each payment was late. The rate changes every quarter (it’s been around 8% annually lately). The IRS will calculate it and send you Notice CP23. You can also calculate it yourself using Form 2210, which you’d attach to your tax return if you think you qualify for an exception.
Frequently Asked Questions (FAQ)
My income is crazy unpredictable, a windfall in Q4, nothing in Q1. Won’t I get penalized?
Not if you use the “Annualized Income Method.” This is done on Form 2210, Schedule AI. It lets you calculate each quarter’s payment based on your actual income earned up to that point in the year, rather than assuming it was equal each quarter. It’s perfect for seasonal businesses or freelancers with one big project. It’s complicated, so tax software or a pro can help.
Can I just wait and pay it all on April 15?
You can, but you’ll definitely owe a penalty. The penalty is charged for each quarter you were short. Paying everything in April only covers the Q4 payment; you’d be late for Q1, Q2, and Q3, and owe penalties for those periods.
I have a W-2 job. Can I just increase my withholding to cover my side hustle taxes?
YES, and this is the smartest move for many people. Withholding from your paycheck is treated as if it was paid evenly throughout the year. You can submit a new Form W-4 to your employer and put a specific dollar amount in Line 4(c) for “extra withholding.” This counts toward your estimated tax requirement and means you don’t have to make separate quarterly payments.
What if I overpay?
You get a refund when you file your tax return. No penalty, but you gave the government an interest-free loan. It’s better to aim to be close.
Do I have to do this for state taxes too?
Almost always, YES. If your state has an income tax, it almost certainly has its own estimated payment requirements and deadlines. You need to check with your state’s revenue department and make separate payments to them. The federal payment does not cover your state.
Shouldn’t my accountant be doing this for me?
They should be telling you how much to pay, but you are responsible for actually making the payment. A good accountant will calculate your amounts and send you reminders. Some firms offer a service where they make the payments for you for an additional fee. Don’t assume—ask them what their process is.
I already missed the April and June deadlines. Am I screwed?
Not screwed, but you need to act now. The penalty clock is ticking. Make a catch-up payment immediately that covers what you should have paid for Q1 and Q2. Then get back on track for September and January. Making a late payment is always better than making no payment.
If you make money outside of a W-2 job, estimated tax payments are part of your financial life. The single best habit you can build is to open a separate savings account labeled “TAXES.” Every single time you get paid from a client, a gig, or your business, immediately transfer 25-40% of that deposit into the tax account. Use that money to make your quarterly payments. It is also advisable to hire a professional to help you with calculations. This system prevents the panic of having spent your entire year’s income and facing a five-figure tax bill with empty pockets. It’s not glamorous, but it’s the foundation of being a solvent, self-employed professional.