How to File Quarterly Estimated Taxes as a New Consulting Firm

2026-08-21

Learn the step-by-step process for filing quarterly estimated taxes as a new consulting firm, including deadlines, calculations, and payment methods.

If you’ve started a consulting firm, you’re now responsible for paying taxes on your income throughout the year, not just at tax time. The IRS requires quarterly estimated tax payments if you expect to owe at least $1,000 in tax for the year. This guide walks you through the exact steps to calculate, file, and pay your quarterly estimated taxes as a new consulting firm.

Step 1: Determine If You Need to Pay Estimated Taxes

Most new consulting firms operate as sole proprietors, LLCs, or S-corps, and all are subject to estimated tax rules. You must make quarterly payments if you expect to owe at least $1,000 in federal tax after subtracting withholding and credits. Since consultants typically have no withholding, this threshold is almost always met.

Additionally, if you had a tax liability last year, you may need to pay even if you expect to owe less this year. The safe harbor rule: pay 100% of last year’s tax liability (or 110% if your adjusted gross income was over $150,000) to avoid penalties.

Step 2: Estimate Your Annual Income and Deductions

Start by projecting your total consulting income for the year. Use your current contracts, invoices, and expected new business. Then subtract business expenses: home office, software, travel, marketing, and professional fees. The result is your estimated taxable income.

For example, if you expect $120,000 in revenue and $30,000 in expenses, your net income is $90,000. You’ll pay self-employment tax (15.3%) on this amount, plus income tax at your marginal rate.

Step 3: Calculate Your Estimated Tax

Use IRS Form 1040-ES to calculate your estimated tax. The form includes a worksheet that walks you through:

Adjusted gross income (AGI) projection
Standard deduction (for 2026, single filers get $15,000, married filing jointly get $30,000)
Taxable income
Income tax (use the 2026 tax brackets: 10%, 12%, 22%, 24%, 32%, 35%, 37%)
Self-employment tax (15.3% of net earnings)
Total estimated tax for the year

Then divide by 4 to get your quarterly payment amount. For the example above, with $90,000 net income, your self-employment tax is $13,770, and income tax might be around $12,000, totaling roughly $25,770. Quarterly payments would be about $6,442.

Step 4: Know the Quarterly Deadlines

Quarterly estimated tax payments are due on:

April 15 (for income earned January 1 through March 31)
June 15 (April 1 through May 31)
September 15 (June 1 through August 31)
January 15 of the following year (September 1 through December 31)

If a deadline falls on a weekend or holiday, the payment is due the next business day. Mark these dates on your calendar now.

Step 5: Choose a Payment Method

You have several ways to pay quarterly estimated taxes:

IRS Direct Pay: Free, allows bank account payments, no account needed
EFTPS (Electronic Federal Tax Payment System): Free, requires enrollment, good for businesses
Credit/debit card: Convenient but fees apply (around 1.85% to 2.9%)
Mail with Form 1040-ES voucher: Use if you prefer paper, but allow extra time

For state taxes, check your state’s revenue department website for similar options.

Step 6: Track Payments and Adjust

Keep a record of each payment you make. You’ll need this for your annual tax return (Form 1040). If your income changes significantly during the year, you can adjust your next quarterly payment. For instance, if you land a big contract, increase your payment to avoid underpayment penalties. Conversely, if business slows, you can reduce payments, but be careful not to fall below the safe harbor.

Step 7: Avoid Common Penalties

The IRS charges penalties for underpayment, even if you pay by the deadline. To avoid this:

Pay at least 90% of your current year’s tax liability
Or pay 100% of last year’s liability (110% if AGI over $150,000)
If your income is uneven, consider annualizing your income using Form 2210

If you miss a deadline, pay as soon as possible. The penalty is based on the amount owed and the time it’s late, typically around 0.5% per month.

FAQ

Q: What if I don’t pay quarterly estimated taxes? A: You’ll likely face an underpayment penalty, which is calculated on Form 2210. The penalty is roughly 0.5% of the unpaid amount per month, plus interest. It’s avoidable by making timely payments.

Q: Can I pay estimated taxes from my business account? A: Yes, you can pay from any bank account. For sole proprietors, it’s common to pay from a personal account, but using a business account is fine. Just ensure you track the payment for tax purposes.

Q: Do I need to file a separate tax return for my consulting firm? A: It depends on your business structure. Sole proprietors report on Schedule C of their personal return. LLCs (single-member) do the same. S-corps and partnerships file separate returns (Form 1120-S or 1065), but estimated taxes are still paid by owners.

Q: What if my income is irregular? A: You can use the annualized income installment method on Form 2210. This allows you to pay lower amounts early in the year and higher amounts later, matching your actual income. It’s more complex but can reduce penalties.

The bottom line

Filing quarterly estimated taxes as a new consulting firm is straightforward once you understand the process. Estimate your income, calculate your tax using Form 1040-ES, and pay by the four deadlines. Use IRS Direct Pay or EFTPS for convenience. Track your payments and adjust as your income changes. By staying on top of these payments, you’ll avoid penalties and keep your business in good standing with the IRS. If you’re unsure about calculations, consult a tax professional; the cost is worth the peace of mind.