The Quarterly Tax Secret Every Solo Tradesperson Needs to Know
A solo electrician makes $95,000 in net income in a good year. He pays $14,535 in self-employment tax. Then income tax. Then state income tax. He was not expecting that. He did not set aside enough. He owes the IRS $22,000 in April. Here is how to not be that guy.
The Double Tax That Surprises Everyone
When you work for an employer, you pay 7.65% of your wages in FICA (Social Security and Medicare). Your employer pays another 7.65% — you never see it. When you are self-employed, you pay both halves: 15.3% of net self-employment income. On $80,000 of net income, that is $12,240 before you pay a dollar of income tax. It is the number that surprises every solo tradesperson in their first year of self-employment.
Quarterly Payments Are Not Optional
Employees have withholding. Self-employed people pay estimated taxes quarterly. If you do not pay enough quarterly, the IRS charges an underpayment penalty calculated daily. The safe harbor: pay 100% of last year’s tax liability (or 110% if your income was over $150,000), spread across four quarterly payments. If your income is growing, use 90% of current year projected tax as your target instead — it usually requires less true-up in April.
The Set-Aside Rule
Every check you cash: put 25–30% in a separate savings account immediately. This is not your money. It is the government’s money that you are temporarily holding. Treat it like a bill that comes due in March, June, September, and December. The tradespeople who handle taxes well do not make complex quarterly projections — they set aside a fixed percentage consistently and the math works out.
Deductions That Actually Reduce SE Tax
Every legitimate business deduction reduces net self-employment income and therefore your SE tax liability. Vehicle costs (actual or mileage), tools and equipment, home office, health insurance premiums (100% deductible for self-employed), and retirement contributions (SEP-IRA allows up to 25% of net income, maximum $69,000 for 2024) all reduce the SE tax base. Use the Self-Employment Tax Estimator to run quarterly projections with your income and deductions — it shows SE tax, estimated income tax, and the quarterly payment amount you need to make to stay penalty-free.
Frequently Asked Questions
What is self-employment tax and why is it so high?
Self-employment tax is 15.3% of net self-employment income (12.4% Social Security + 2.9% Medicare). Employees split this with their employer — each pays 7.65%. Solo tradespeople pay both halves. On $80,000 of net income, SE tax is $11,304 before income tax. You can deduct half of SE tax from gross income, reducing your income tax slightly.
When are quarterly estimated tax payments due?
Quarterly estimated payments are due April 15 (for Jan-Mar), June 15 (for Apr-May), September 15 (for Jun-Aug), and January 15 of the following year (for Sep-Dec). Missing or underpaying these triggers an underpayment penalty calculated daily at the federal short-term rate plus 3%.
How much should I set aside for taxes as a solo tradesperson?
A conservative estimate: set aside 25–30% of every payment you receive. This covers SE tax (15.3%), federal income tax (12–22% for most tradespeople), and provides a buffer for state income tax. Keep this in a separate savings account and do not touch it until quarterly payments are due.
What deductions reduce self-employment tax?
SE tax is calculated on net self-employment income (revenue minus legitimate business deductions). Every valid business deduction reduces your SE tax basis: vehicle costs, tools and equipment, home office if applicable, health insurance premiums (100% deductible for self-employed), retirement contributions (SEP-IRA, Solo 401k). Good recordkeeping on deductions reduces your SE tax dollar for dollar on the deduction amount × 15.3%.