Most content on 1099 physician taxes focuses on deductions. For anesthesiologists working locums, crossing state lines, or earning a high 1099 income, the larger issue is tax structure. Estimated taxes, S-Corp election, and multi-state filing rules all affect each other. Getting the structure right before the return is due saves time, reduces self-employment tax exposure, and avoids IRS penalties that are expensive to fix after the fact.
Unlike W-2 employment, where your employer sends a portion of each paycheck to the IRS on your behalf, 1099 status means that responsibility falls entirely on you. The self-employment tax rate is 15.3% on net earnings up to the Social Security wage base, which was $176,100 for the 2025 tax year. That figure adjusts annually, so if you’re planning ahead for 2026 income, confirm the current threshold directly with the IRS at irs.gov or the SSA at ssa.gov. The 2.9% Medicare portion applies to all net earnings with no cap.
The IRS requires quarterly estimated payments on April 15, June 15, September 15, and January 15. Missing those deadlines or underpaying triggers an underpayment penalty calculated at the federal short-term interest rate plus three percentage points. For 2025, that rate is 8%, compounding each quarter in which payments fell short.
The safe harbor rule gives you a defined target to avoid IRS penalties. If your 2025 estimated payments equal at least 100% of your 2024 tax liability, the IRS won’t assess a penalty even if you owe more at filing. If your 2024 adjusted gross income exceeded $150,000, that threshold rises to 110% of your prior-year liability.
Quick tip: If you’re not sure what to pay each quarter, take your total 2024 federal tax liability, multiply it by 110% if your income was above $150,000, and divide by four. That number is your quarterly floor while you finalize 2025 income projections. |
For physicians transitioning from W-2 to 1099 mid-year, there’s no prior-year 1099 baseline to reference. The annualized income installment method on IRS Form 2210 allows you to match each quarterly payment to the income actually earned in that period, rather than dividing a full-year estimate evenly across four quarters. This is particularly useful when locum income is weighted toward the second half of the year.
Something that trips people up: Quarterly payments are not retroactive. Underpaying in Q1 and Q2 and catching up in Q4 doesn’t remove the penalty for those earlier periods. The IRS calculates it quarter by quarter.
Locum tenens assignments mean income earned in multiple states. Each state where you physically worked has a claim on that income, which means Georgia-based physicians need to file a non-resident return in each of those states in addition to their Georgia resident return.
Most states determine taxable income by multiplying the number of days worked in that state relative to total days worked by the total earned income. Some states use a wage-based allocation method instead. The IRS and individual states aren’t coordinated on this, and misapplying the allocation method is one of the most common multi-state filing mistakes.
Georgia provides a credit for taxes paid to other states on Georgia Form 500, Schedule 3. The credit reduces your Georgia tax liability dollar-for-dollar up to the amount Georgia would have taxed on that same income. It offsets the liability; it doesn’t produce a refund if another state’s rate exceeds Georgia’s flat 5.19% for 2025. Florida and Tennessee have no individual income tax, so assignments in those states don’t require a state return.
Quick tip: Keep a log of days worked per state throughout the year. You’ll need it for income allocation on each non-resident return, and it’s much harder to reconstruct after the fact. A basic spreadsheet by engagement date and location is enough. |
A separate issue applies to your tax home classification. If a locum assignment is expected to last less than one year, the IRS treats it as temporary. That preserves your Georgia tax home status and allows per diem deductions for lodging and meals under IRS Publication 463. If the assignment becomes indefinite, those deductions disappear, and state tax treatment may change. Physicians on longer contracts often miss this distinction until filing.
For physicians working in three or more states, the credit calculations and allocation rules are so complex that errors often cost more in penalties or missed credits than professional help would. The accounting for anesthesiologists page at Accolade Accounting explains what that support looks like in practice.
The S-Corp election reduces self-employment tax by splitting 1099 income between a W-2 salary and an owner distribution. Salary is subject to payroll taxes. Distributions are not. The tax savings come from removing the distribution portion entirely from self-employment tax exposure.
At $245,000 in net 1099 income, paying yourself a reasonable salary of $150,000 and taking $95,000 as a distribution removes $95,000 from self-employment tax exposure. Without the S-Corp, the full $245,000 would generate roughly $28,940 in self-employment tax. With the election, payroll taxes apply only to the $150,000 salary, reducing that figure to approximately $22,950. The difference is close to $5,990 annually before payroll administration costs are factored in. The break-even point for most physicians falls around $80,000 to $100,000 in net 1099 income. Below that threshold, the administrative costs of payroll, quarterly deposits, and a separate corporate return tend to exceed the savings.
The IRS requires S-Corp owners who perform services for the corporation to pay themselves a reasonable salary. For anesthesiologists, figures in the $180,000 to $250,000 range are generally defensible depending on specialty, setting, and hours worked. Physician salary survey data from sources like MGMA support this range.
Paying yourself $40,000 to maximize distributions on $400,000 in income may raise eyebrows. The IRS has a consistent history of reclassifying S-Corp distributions as wages when the salary structure can’t be supported. The IRS guidance on S-Corp compensation describes the standard applied. Once flagged, the reclassification triggers back payroll taxes, interest, and penalties on the reclassified amounts.
The S-Corp election for anesthesiologists page on Accolade Accounting explains the compliance requirements before committing to the structure.
Quick tip: S-Corp election isn’t permanent. Revocation has its own rules and timing requirements. Treat it as a decision to review annually based on that year’s income, not a one-time setup. |
Estimated taxes, multi-state filing, and S-Corp election don’t operate independently. Each one changes the calculation for the others. That interaction is where most generic online content falls short.
Once you elect S-Corp status, your income flows through two channels. Salary goes through the payroll system with withholding applied. Distributions don’t carry withholding and still require quarterly estimated payments. A physician who assumes payroll withholding covers the full tax obligation will find a balance due at filing. The quarterly estimated payment calculation changes the moment the S-Corp is active, and it’s worth adjusting payment amounts immediately rather than catching up at year-end.
Some states require an S-Corp with non-resident shareholders performing work in their state to register separately, file a corporate-level return, or withhold taxes on the shareholders’ behalf. A Georgia-based physician working locum assignments in a state with entity-level pass-through taxes may face registration and filing obligations for the corporation itself, not just a personal non-resident return. These obligations exist regardless of whether the physician anticipated them when making the S-Corp election in Georgia.
The most common gap isn’t a calculation error. It’s treating each decision as a separate question. A physician who elects S-Corp status, then takes a multi-state locum contract, then adjusts distributions mid-year, is now dealing with three moving variables at once. Estimated payments need to reflect the new income split. Non-resident returns need to account for the corporate structure. The Georgia credit calculation may shift based on how income is allocated between the S-Corp and Schedule E. Handling these decisions sequentially, without accounting for how each affects the others, is where tax exposure accumulates.
Incomplete documentation is the most common reason anesthesiologist returns take longer than expected or require amendments. Physicians who worked through staffing agencies in multiple states sometimes receive 1099-NEC forms late or discover that state withholding was handled inconsistently across engagements.
Document | Purpose |
1099-NEC from each facility or staffing agency | Reports self-employment income by source |
Records of days worked in each state | Supports income allocation for non-resident returns |
Quarterly estimated payment records | Required for Form 2210 and state penalty calculations |
Business expense receipts | Supports deductions on Schedule C or S-Corp return |
Payroll records if operating an S-Corp | Required for W-2 filing and salary documentation |
Per diem logs for temporary assignments | Supports lodging and meal deductions under IRS Publication 463 |
If you’re still working through the entity setup side, the guidance on business setup for 1099 doctors at Accolade Accounting explains the structure and registration decisions before your first contract starts.
Disclaimer: This article is for informational purposes only and is not intended as tax advice. Tax situations vary, and IRS rules can change. Always consult with a qualified tax professional regarding your specific circumstances.
