Guide topic
Deductions, and lowering the bill
What genuinely comes off your taxable income, and what the rules ask of you in return.
United States only. These guides cover US federal tax. They do not apply to Canada, the UK or other countries.
A deduction is not a discount. Deducting a $2,000 laptop does not save you $2,000; it removes $2,000 from the income you are taxed on, so the saving is that amount times your combined marginal rate — often somewhere around a third of it. Getting that relationship right is what stops people buying things in December they did not need.
The deductions worth the most to self-employed people are rarely the exciting ones. The self-employment tax deduction, the QBI deduction and a retirement contribution are all large, all automatic-ish, and all invisible on a receipt. The equipment and home-office questions people actually search for are usually worth less than any of them.
Everything here is US federal. Where a rule has a real condition attached — exclusive use, a written log, a percentage limit — the guide says so plainly, because a deduction you cannot support is worse than one you never claimed.
13 guides, in the order they usually matter
- The deductions self-employed people most often miss The home office rule people wrongly fear, the mileage rate that beats actual costs, half your phone bill, and retirement accounts that dwarf an IRA.
- The QBI deduction: 20% off your business income, explained Most self-employed people can deduct 20% of business profit with no spending and no receipts. How it works in 2026, including the new $400 minimum.
- The home office deduction: the audit myth, and which method pays more It does not trigger audits. The simplified method caps at $1,500, the actual method often doubles it, and exclusive use is stricter than people think.
- Can you deduct a laptop? And should you deduct it all at once? Yes, on the business-use share. The real question is whether to write it off in one year or spread it — and in a low-profit year, spreading it is worth more.
- Mileage or actual costs? The 2026 vehicle deduction, with the mid-year rate change The IRS raised the mileage rate part-way through 2026, so the year has two rates. How to split your log, and when actual costs win.
- The self-employed health insurance deduction, and the trap inside it One of the largest deductions available to a freelancer, and the one most often filed on the wrong form. It also does not reduce self-employment tax.
- Solo 401(k) or SEP-IRA? The 2026 numbers, and the deadline that decides it Both cap at $72,000 in 2026, but the solo 401(k) gets there on far less income. The catch is a December 31 deadline the SEP does not have.
- The SEP-IRA “25% rule”: why your real limit is closer to 18% The 25% is of compensation, and a self-employed person has none. After the circular adjustment the real ceiling is about 18.6% of net profit.
- Can you have a solo 401(k) and a job with a 401(k)? Yes — but one limit is per person and the other is per employer, and mixing them up is how people over-defer. Which number applies to which pot.
- How late can you still open a retirement account for last year? A SEP-IRA can be opened and funded after the year ends — an IRA cannot. Four plans, four different cut-offs, and only some of them move with an extension.
- Is a coworking space deductible? And can you claim both? Fully deductible, and simpler than a home office. But claiming both in the same year is possible — and the interaction changes which of your car journeys count.
- Can you deduct courses, books and conferences? If it improves skills you already use, yes. If it qualifies you for a new profession, no — and that line is stricter than most freelancers assume.
- What if you have no receipts? Not automatically lost. Bank records and reasonable reconstruction carry most categories — but four kinds of expense have far stricter rules.