Contractor vs Employee Compensation

Contractors pay estimated taxes quarterly (April 15, June 15, September 15, January 15) using IRS Form 1040-ES. You estimate your annual tax liability and pay roughly 25% each quarter to avoid underpayment penalties.

Unlike employees who have taxes withheld from each paycheck, contractors must calculate and send tax payments four times per year. This includes both income tax and self-employment tax. The IRS expects you to pay at least 90% of your current year tax (or 100% of last year's tax) through estimated payments to avoid penalties. Many contractors set aside 25-30% of each payment received into a separate account for taxes.

Most independent contractors bill 30-35 hours per week even if they work 40+. The remaining time goes to finding clients, invoicing, admin, professional development, and gaps between contracts.

A common mistake when calculating contractor rates is assuming 40 billable hours per week, 52 weeks per year (2,080 hours). In reality, contractors lose time to: unpaid vacation and sick days (2-4 weeks), administrative work (5-10 hours/week), business development and marketing (2-5 hours/week), and gaps between contracts. A realistic estimate is 1,500-1,800 billable hours per year for most independent contractors.

Marketplace health insurance cost depends on your income, age, state, and plan tier. For a 35-year-old in Texas earning $126,000, a Silver plan costs approximately $500 to $650 per month before any subsidy. Many contractors earning above 400% of the Federal Poverty Level ($63,840 for a single person in 2026) do not qualify for a premium subsidy.

The calculator estimates your marketplace health insurance cost using the Affordable Care Act (ACA) subsidy formula based on your projected contractor income. Bronze plans with Health Savings Account (HSA) eligibility are a common strategy for healthy contractors who want lower premiums and tax-advantaged savings. Health insurance is often the single largest new expense when leaving employment, because employer plans typically cover 79% of the premium cost that you must now pay in full.

Self-employment tax is 15.3% of net earnings — it covers Social Security (12.4%) and Medicare (2.9%). Employees only pay half (7.65%) because their employer pays the other half. The Social Security portion applies to the first $176,100 of earnings in 2025.

When you're employed, you see 7.65% withheld from your paycheck for FICA, and your employer quietly pays another 7.65% on your behalf. As a self-employed contractor, you pay both halves — the full 15.3%. However, you can deduct the employer-equivalent portion (7.65%) when calculating your adjusted gross income, which reduces your income tax slightly. An additional 0.9% Medicare tax applies to earnings above $200,000 for single filers.

Contractors cover costs that employers pay for employees: the full 15.3% self-employment tax (vs. 7.65% for employees), health insurance, retirement contributions, paid time off, and business expenses. These add 40-70% to the base salary equivalent.

As an employee earning $120,000, your employer pays ~$9,180 in Federal Insurance Contributions Act (FICA) taxes, employer-provided health insurance worth $7,400 (national average for single coverage), $4,800 in 401(k) matching, and gives you 20+ days of paid leave worth ~$9,200. That's over $35,000 in hidden compensation. As a contractor, you pay all of this yourself from your hourly rate, plus business expenses like liability insurance, accounting, and equipment.