Most freelancers know self-employment tax exists. Fewer know what it actually costs them, and almost none built it into their rate correctly when they started.
If you don’t account for SE tax in your rate, you’re subsidising your clients. On $80,000 in net profit, SE tax alone runs about $11,300, before a dollar of income tax.
This article explains exactly how the calculation works, why it catches people off guard, and what to do about it.
What self-employment tax actually is
When you work as an employee, Social Security and Medicare taxes are split between you and your employer. You pay 7.65%. Your employer pays the other 7.65%. You never see the employer half — it disappears before your paycheck is calculated.
When you’re self-employed, you pay both halves yourself. That’s the 15.3%:
- Social Security: 12.4% (on income up to $184,500 in 2026)
- Medicare: 2.9% (no income cap)
As a freelancer, you’re acting as both the employee and the employer. Both halves come out of your pocket.
The 92.35% multiplier
SE tax isn’t applied to your full net profit. It’s applied to 92.35% of your net profit. The IRS allows you to deduct the employer-equivalent portion of SE tax before calculating the tax itself, a partial offset that slightly reduces what you owe.
The formula:
SE tax = net profit × 0.9235 × 0.153
On $80,000 net profit:
$80,000 × 0.9235 = $73,880 (adjusted net earnings) $73,880 × 0.153 = $11,304 in SE tax
Most people instinctively calculate 15.3% of $80,000 and get $12,240. The 92.35% adjustment brings it to $11,304. Not a dramatic difference, but use the correct formula if you’re doing your own math.
SE tax and income tax are separate obligations
This is where most freelancers get caught short. SE tax and income tax are not the same bill. You pay both.
On the same $80,000 net profit, a California freelancer:
| Tax | Calculation | Amount |
|---|---|---|
| SE tax | $80,000 × 92.35% × 15.3% | $11,304 |
| SE tax deduction | Reduces taxable income by $5,652 (half of SE tax) | — |
| Federal income tax | 2026 brackets on $46,599 taxable income | $5,344 |
| California state tax (9.3%) | ($80,000 − $5,652) × 9.3% | $6,914 |
| Total tax burden | $23,562 | |
| After-tax income | $56,438 |
A California freelancer earning $80,000 in net profit takes home $56,438. That’s a combined tax rate of 29.5%.
The federal income tax figure deserves explanation. $5,344 on roughly $80,000 of net profit looks low until you see how it’s computed. Three deductions come off before the brackets apply: the $5,652 SE deduction, the $16,100 standard deduction, and the 20% QBI deduction for self-employed filers. What’s left is $46,599 of taxable income, taxed at 10% on the first $12,400 and 12% on the rest. There is no flat rate applied to everything.
In a no-income-tax state like Texas or Florida, the total drops to $16,648, about 20.8% of gross. If you priced your services expecting to keep $80,000, you’d take home $56,000–$63,000 depending on where you live. That gap is SE tax doing its work.
The ChargeWhat rate calculator runs the full calculation for your income and state automatically.
Why a $100,000 salary and $100,000 in freelance revenue are not the same thing
This is the comparison most new freelancers never make. They look at their day rate, convert to an annual equivalent, and feel good about the number. The number misleads.
As an employee earning $100,000 in a no-income-tax state:
- Your employer pays ~$7,650 in payroll taxes on your behalf
- You receive paid time off, often health insurance, and employer retirement contributions
- Your take-home (standard deduction, 2026 brackets) is roughly $79,000
As a freelancer generating $100,000 in net profit in the same no-income-tax state:
- You pay SE tax of ~$14,130
- You pay health insurance out of pocket; individual coverage averaged $450–$600/month in 2026
- Every week of vacation is a week of zero revenue
- With $450/month in health insurance, your take-home is roughly $73,000
To match the $79,000 take-home of the salaried employee, a freelancer with $450/month in health insurance needs to generate approximately $109,000 in net profit, about 9% more.
The premium grows with health insurance cost and time off. The tax math under 2026 rules is less punishing than many rate guides suggest. The QBI deduction and standard deduction do real work. Health insurance is the bigger gap driver at typical freelance income levels.
The quarterly estimated payment requirement
SE tax isn’t withheld automatically. You’re required to pay estimated taxes four times a year:
- April 15 (Q1: January–March)
- June 15 (Q2: April–May)
- September 15 (Q3: June–August)
- January 15 (Q4: September–December)
Underpaying during the year triggers an underpayment penalty at filing even if you pay the full amount by April 15. The penalty rate in 2026 is 8% annualised, avoidable with a simple system.
Set aside 25–30% of every payment you receive into a separate savings account. Make quarterly payments from that account. Adjust the percentage up if you’re in a high-tax state. That’s the whole system. Start it from your first invoice.
The SE tax deduction
One partial offset worth knowing: you can deduct half of your SE tax from your gross income before calculating income tax. It’s automatically available to self-employed individuals, no itemising required.
On $80,000 net profit with $11,304 in SE tax:
- Deductible amount: $11,304 ÷ 2 = $5,652
- This reduces your federal taxable income by $5,652
- At the 12% marginal bracket this income falls into, that saves roughly $678 in federal income tax
It doesn’t eliminate SE tax. It partially offsets the income tax burden. The 92.35% multiplier already accounts for this in the SE tax calculation itself.
Three things to do with this information
Build SE tax into your rate from day one. Not as an afterthought. Not when you realise you’re short at tax time. SE tax is not optional and it doesn’t go away. Every dollar your rate fails to cover is a dollar coming out of your take-home. Most freelancers who underprice do so because they set a rate before they ran this math.
Open a separate tax account. Set aside 25–30% of every invoice payment the day it clears. Treat it as untouchable. The freelancers who get into trouble at tax time are the ones who spent money they were holding for the IRS.
Calculate your actual minimum rate. Run the real numbers: your state tax rate, your health insurance cost, your realistic billable hours, your profit buffer. The ChargeWhat freelance rate calculator runs the full calculation for free, with no signup. It handles the SE tax math correctly and shows exactly where every dollar of your rate goes.
Key numbers for 2026
- SE tax rate: 15.3% (12.4% Social Security + 2.9% Medicare)
- Applied to: 92.35% of net profit
- Social Security wage base: $184,500
- Quarterly payment dates: April 15, June 15, September 15, January 15
- Safe harbor rule: Pay at least 100% of prior year’s tax liability to avoid underpayment penalties (110% if prior year AGI exceeded $150,000)
- Suggested set-aside rate: 25–30% of gross receipts, more in high-tax states
This article is for informational purposes only and does not constitute tax advice. Tax rules change annually and individual situations vary. Consult a CPA or enrolled agent before making decisions about estimated payments or tax planning.