Quarterly Estimates: Exact Steps for Each Quarter

November 13, 2025

If you have self-employment income, 1099 income, side income, or run a practice, you’re responsible for quarterly estimated taxes.

The IRS expects you to pay taxes as you earn.
Not once a year.
Not when convenient.
Every quarter.

Here is the exact checklist you can follow for all four quarters—clear, simple, and repeatable.

Before You Start: Know Your Income Type

If you have W-2 income only, quarterly estimates may not apply.
If you earn 1099 income, use this guide:
→ 1099 Contractor Tax Guide for Physicians

If you run your own practice, make sure your entity structure is correct:
→ Best Tax Structure for Doctors 2025

Now, let’s go quarter by quarter.

Quarter 1 (Jan 1 – Mar 31)

Payment due by April 15

Step 1 — Add up all income from Jan–Mar

Include:

1099 earnings
Practice revenue
Side business income
Non-clinical consulting or advisory work
→ How Doctors Are Increasing Income With Non-Clinical Side Businesses

Step 2 — Calculate your estimate

Use the safe-harbor rule:

100% of last year’s tax (110% if income > $150k)
OR
90% of current year tax

Step 3 — Apply deductions

Don’t forget:

Business mileage
CME + conference travel
→ Business Travel & Vacation Deductions for Doctors

Step 4 — Pay using IRS Direct Pay

Quarter 2 (Apr 1 – May 31)

Payment due by June 15

This quarter is short.
Income periods are uneven, but the IRS expects payment anyway.

Step 1 — Update your new earnings

If income jumped, adjust estimates upward now (not in Q4).

If you work in a high-tax state, monitor how this affects your withholding strategy:
→ High State Income Taxes & Retirement Planning

Step 2 — Recalculate your running total

Use your year-to-date income to correct any Q1 underpayment.

Step 3 — Pay early if traveling

Quarter 2 is the most frequently missed deadline.
Plan ahead if you’re out of town for medical seminars.

Quarter 3 (Jun 1 – Aug 31)

Payment due by September 15

This is the “correction quarter.”
You see how your year is shaping up and adjust accordingly.

Step 1 — Review revenue trends

If your practice hit a growth streak, increase estimates now.

If markets dropped and you harvested losses, adjust your taxable gains:
→ Market-Loss Tax Saving Opportunities

Step 2 — Factor in new side income

Telehealth, advisory, and outside consulting count.
Some physicians dramatically underpay because they forget about new income streams:
→ How Physicians Are Increasing Income With Non-Clinical Side Businesses

Step 3 — Adjust for travel deductions

If you had heavy travel this year:
→ Business Travel Deductions for Doctors 2025

You may owe less than expected.

Quarter 4 (Sep 1 – Dec 31)

Payment due by January 15 (following year)

This is the most strategic quarter of all.

Step 1 — Finalize total income

Include:

Last-minute consulting
Year-end bonuses
Late insurance reimbursements
Real estate or investment income

Step 2 — Maximize year-end tax moves

This is where you reduce your taxable income before year-end.

Start here:
→ Doctor Tax Saving Strategies 2025

Step 3 — Review entity salary/distributions

If you’re an S-corp physician owner, your compensation strategy affects estimates:
→ Best Tax Structure for Doctors 2025

Step 4 — Make the year’s final estimate by Jan 15

Annual Checklist (Use This Every Year)

Track all 1099 + practice income
Adjust estimates every quarter
Use safe-harbor rule to avoid penalties
Log all business travel deductions
Run retirement plan contributions before year-end
Keep quarterly payment confirmations
Review your structure annually

FAQ

1. What happens if I skip a quarterly payment?
The IRS charges an underpayment penalty, even if you pay everything by April.

2. Are the due dates the same every year?
Yes — except when they fall on weekends or federal holidays.

3. Does W-2 income count toward estimated taxes?
Yes. Your withholding reduces what you owe for quarterly estimates.

4. Do I still need to pay quarterly if I use Safe Harbor?
Yes. Safe Harbor protects you from penalties but still requires payments.

5. Can deductions reduce my quarterly payments?
Yes — mileage, travel, CME, and business expenses lower taxable income.

Ready to talk strategy? Start here.

Visit contact physiciantaxsolutions.com to schedule a consultation and learn how we can help you take control of your tax strategy today.

This post serves solely for informational purposes and should not be construed as legal, business, or tax advice. Individuals should seek guidance from their attorney, business advisor, or tax advisor regarding the matters discussed herein. physiciantaxsolutions.com assumes no responsibility for actions taken based on the information provided in this post.