If you have a side hustle — whether it is freelance writing, driving for DoorDash, selling on Etsy, tutoring, or any other income-generating activity — you are running a business in the eyes of the IRS. That means you owe self-employment tax on your profits, but it also means every legitimate business expense reduces the income you are taxed on.
Most side hustlers leave hundreds or even thousands of dollars in deductions on the table every year — not because the deductions do not exist, but because they did not track their expenses carefully enough to claim them. This guide fixes that.
The Tax Reality of Side Hustle Income
When you earn income from a side hustle, the IRS treats you as self-employed. This has two important implications:
You owe self-employment tax. Self-employment tax is 15.3% of your net profit (12.4% for Social Security, 2.9% for Medicare). This is in addition to your regular income tax. If your side hustle generates $10,000 in profit, you owe approximately $1,530 in self-employment tax before income tax is calculated.
You can deduct business expenses. Every dollar you spend on legitimate business expenses reduces your net profit — which reduces both your self-employment tax and your income tax. A $1,000 business expense deduction saves you approximately $153 in self-employment tax plus your marginal income tax rate on that $1,000.
This is why expense tracking is not optional for side hustlers — it is the difference between paying taxes on your revenue and paying taxes on your actual profit.
What Counts as a Side Hustle Business Expense?
The IRS allows deductions for expenses that are "ordinary and necessary" for your business. Here are the most common deductions by side hustle type:
| Expense Category | Examples | Who Claims It |
|---|---|---|
| Home office | Dedicated workspace square footage | Freelancers, remote workers, online sellers |
| Vehicle/mileage | Miles driven for business purposes | Delivery drivers, real estate agents, contractors |
| Equipment | Laptop, camera, microphone, tools | Creators, photographers, contractors |
| Software & subscriptions | Design tools, accounting software, cloud storage | Freelancers, creators, online sellers |
| Marketing & advertising | Facebook ads, website hosting, business cards | All side hustlers |
| Professional services | Accountant fees, legal fees | All side hustlers |
| Education & training | Courses, books, conferences in your field | All side hustlers |
| Phone & internet | Business-use percentage of your bill | All side hustlers |
| Supplies & materials | Packaging, raw materials, office supplies | Sellers, crafters, contractors |
| Platform fees | Etsy listing fees, PayPal fees, Stripe fees | Online sellers |
The Most Overlooked Side Hustle Deductions
Mileage. The 2025 IRS standard mileage rate is 70 cents per mile for business driving. If you drive 5,000 miles per year for your side hustle — to meet clients, pick up supplies, attend events — that is a $3,500 deduction. Most side hustlers do not track their mileage and miss this entirely.
Home office. If you have a dedicated space in your home used exclusively and regularly for your side hustle, you can deduct a portion of your rent or mortgage, utilities, and internet based on the square footage of that space relative to your total home. A 150-square-foot office in a 1,500-square-foot home means 10% of your home expenses are deductible.
Phone and internet. If you use your phone and internet for your side hustle, the business-use percentage is deductible. If 40% of your phone use is for business, 40% of your monthly bill is a deductible expense.
Start-up costs. If you started your side hustle this year, you can deduct up to $5,000 in start-up costs in the first year. This includes market research, legal fees for business formation, initial inventory, and website setup costs.
How to Track Side Hustle Expenses Correctly
The IRS requires contemporaneous records — meaning you need to document expenses at the time they occur, not reconstruct them from memory at tax time. A receipt or invoice is the gold standard; bank and credit card statements are acceptable supporting documentation but are not sufficient on their own for all expense types.
The system that works:
- Open a dedicated bank account and credit card for your side hustle. This is the single most important step. When all business transactions flow through one account, tracking becomes dramatically easier and your records are cleaner for the IRS.
- Scan every business receipt immediately with ReceiptSync. The app reads the merchant, amount, date, and category automatically. Create custom categories that match your Schedule C line items: Advertising, Car and Truck Expenses, Office Expenses, Supplies, Utilities, Other Expenses. At tax time, your Schedule C practically fills itself.
- Log mileage in real time. Use the notes field in ReceiptSync or a dedicated mileage log app to record every business trip: date, starting point, destination, purpose, and miles driven.
- Keep a simple income log. Track every payment you receive — from clients, platforms, or customers — with the date, amount, and payer. This is your gross revenue for Schedule C.
Filing Your Side Hustle Taxes
Side hustle income is reported on Schedule C (Profit or Loss from Business) attached to your Form 1040. Your net profit (revenue minus expenses) flows to Schedule SE for self-employment tax calculation and then to your 1040 for income tax.
If your side hustle generates more than $400 in net profit in a year, you are required to file Schedule C and Schedule SE. If you expect to owe more than $1,000 in taxes for the year, you are required to make quarterly estimated tax payments (due April 15, June 15, September 15, and January 15).
Use the 1099 Quarterly Tax Estimator to calculate your estimated payments and avoid underpayment penalties.
Related guides
- How to File Taxes for a Side Hustle in 2026
- Schedule C Expense Categories: Complete Guide
- Best Expense Trackers for 1099 Contractors
- 1099 Quarterly Tax Estimator
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