Last-Minute Freelancer Tax Deductions Before You File

Moves you can still make after year end

• SEP-IRA / traditional IRA contribution. Generally allowed up to the filing deadline and counts for the prior year, lowering taxable income directly. The biggest true last-minute lever.
• HSA contribution if you had an eligible high-deductible health plan, also allowed up to the deadline.

Deductions people forget to claim

• Home office, simplified method is $5 per square foot up to 300 sq ft.
• Mileage, 72.5 cents per business mile for 2026, if you kept a log.
• Self-employed health insurance premiums, deducted above the line.
• The QBI deduction, up to 20% of net business income on Form 1040.
• Phone and internet, the business-use share.
• Startup costs, up to $5,000 in your first year.

Fix your “Other expenses” before filing

Anything dumped into a generic “Other” bucket is a deduction at risk. Take a few minutes to move each expense into its correct Schedule C category so it is fully claimed and clearly documented. If your receipts are already categorized, this is a quick review instead of a scramble.

Not ready? File an extension

An extension gives you six more months to file, but not to pay. Estimate what you owe with the 1099 tax calculator and pay that by the April deadline to avoid interest and penalties.