What self-employment tax actually is
When you had a job, you and your employer split the Social Security and Medicare contributions. You paid 7.65% out of your paycheck, and your employer matched it quietly. You never saw their half because it never passed through your bank account.
As a freelancer, you pay both halves yourself. That is self-employment tax: 12.4% for Social Security plus 2.9% for Medicare, totaling 15.3% of your net earnings from self-employment.
This is on top of federal income tax, not instead of it. It catches most first-year freelancers by surprise because their old tax situation made it invisible.
The full tax picture for a mid-career US freelancer
Here is what the stack looks like for a freelancer earning $100,000 in net self-employment income in the US:
Self-employment tax — 15.3%
Applied to 92.35% of net earnings (that small adjustment is the official IRS calculation). On $100K net, that is roughly $14,130.
Federal income tax — ~17% effective
After the standard deduction, effective rates for this income range land around 17%. On $100K, roughly $17,000.
State income tax — 0% to 10%+
Texas: $0. California: around $7,000–$8,000. New York: similar.
The set-aside percentages that work in practice
From every client payment that hits your account, move a fixed percentage straight to a separate savings account for taxes. This is the single most important cash-flow habit for freelancers, and almost nothing else matters if you get this part right.
No-income-tax states
Set aside 32%. That is Texas, Florida, Washington, Nevada, South Dakota, Wyoming, Alaska, plus Tennessee and New Hampshire, which do not tax earned income.
Most states
Set aside 35%–38%. This covers the majority of US freelancers.
High-tax states
Set aside 40% for California, New York, Hawaii. Oregon reaches about 41% because it has high state income tax and no sales tax to offset it.
Deductions that actually move the needle
Every legitimate business expense you deduct reduces your net self-employment income, which lowers both your income tax and your self-employment tax. Deductions hit twice for freelancers.
Software and subscriptions
Anything you use to run the business: invoicing software, design tools, hosting, productivity apps, domain names. 100% deductible.
Home office
A percentage of your rent, utilities, and internet based on the square footage you use exclusively for work. The simplified method is $5 per square foot up to 300 sq ft.
Phone and internet
The business-use percentage, typically 40–80% depending on how much personal use you make.
Equipment
Laptops, monitors, cameras, office furniture. Section 179 lets you deduct the full cost in the year you buy it, up to a generous limit.
Health insurance premiums
Self-employed health insurance is deductible above the line — you do not need to itemize to get it.
Retirement contributions
A SEP-IRA lets you contribute and deduct up to 25% of net self-employment earnings. A Solo 401(k) can be even higher.
Why expense tracking is the actual tax strategy
There are no magical tax tricks for freelancers. The entire game is logging every legitimate deduction, every week, all year long. The freelancer who owes the least in April is the one who logged $14,000 of deductions consistently instead of the $6,000 the other freelancer managed to reconstruct from credit card statements.
FreelanceFlow's expense tracker is designed for this specifically: log an expense in under 10 seconds with amount, category, date, and an optional note. Every expense you log reduces your running tax estimate in real time. You never have to compile a spreadsheet.
What to do with an accountant (and when)
In your first freelance year, get an accountant for the tax filing itself even if you handle bookkeeping yourself. A decent accountant costs $400–$800 for a freelance return and usually saves more than they cost through deductions you missed.
Give them a clean export of your income and expenses — FreelanceFlow's tax summary is designed to be handed straight to an accountant without reformatting. They file; you stay out of the weeds.