Does a Teen Running a Small Side Hustle Owe Self-Employment Tax?
A teenager mowing lawns, reselling sneakers, or doing freelance design work over the summer can end up making real money, and a parent or the teen themselves starts wondering whether any of that needs to be reported. It feels like a kid thing, but the tax rules don’t actually see it that way once profit adds up.
The short answer
Age has nothing to do with whether self-employment tax applies; net profit does. Once a person’s net earnings from self-employment cross a set annual threshold, self-employment tax, which feeds into the same Social Security funding system that payroll withholding does, generally applies regardless of whether the person is 16 or 46. Below that threshold, self-employment tax typically isn’t owed, though income tax filing rules can still come into play separately.
Why self-employment is treated differently than a regular job
When a teen works a normal part-time job, an employer withholds payroll taxes automatically and the teen never has to think about it. Self-employment works differently because there’s no employer doing that withholding. Instead, the person running the small business, whether it’s selling stuff online or offering a service like tutoring or lawn care, is responsible for tracking income and expenses and figuring out net profit at the end of the year. That net profit, not gross revenue, is what gets measured against the self-employment tax threshold.
What counts as net earnings
- Revenue minus expenses. If a teen sells refurbished bikes for $3,000 total but spent $1,800 on parts and supplies, the relevant number for tax purposes is the $1,200 profit, not the $3,000 in sales.
- Legitimate business expenses reduce the total. Supplies, materials, a portion of related costs like mileage for a service business, and other ordinary expenses tied directly to the activity can generally be subtracted before arriving at net profit.
- Occasional side income is treated differently than an ongoing business. A one-off garage sale or a single freelance gig is usually not treated the same as a repeated, profit-seeking activity, which is the kind of pattern that tends to look like self-employment to tax authorities.
How this differs from a W-2 summer job
A teen with a traditional W-2 job has taxes withheld from each paycheck by the employer, and depending on total income for the year, some or all of that withholding might come back as a refund. A self-employed teen doesn’t have that automatic withholding, which means the responsibility to set money aside for taxes falls on the individual. This is one of the more common surprises: a teen assumes that because they’re young or because the amount feels small, nothing is owed, only to find that the profit crossed the relevant threshold once the year is totaled up.
Filing considerations beyond self-employment tax
Self-employment tax is separate from regular income tax, and a teen can potentially owe one without owing the other, or both, depending on total income for the year. Filing thresholds and rules can also work differently when a teen is claimed as a dependent on a parent’s return. Because these rules involve multiple moving pieces, thresholds, dependency status, and the type of income, it’s generally worth reviewing official guidance or consulting a tax professional for the specific situation rather than assuming last year’s rules or a friend’s experience will apply directly.
What records actually matter
- Basic bookkeeping helps regardless of the final tax outcome. Even a simple spreadsheet tracking money in, money out, and what it was for makes it far easier to determine net profit accurately, and knowing how long tax records generally need to be kept helps avoid tossing documentation too soon.
- Receipts for expenses matter if they’re going to be subtracted from revenue. Without documentation, it’s harder to justify deducting supply costs or other expenses.
- Consistency over the year adds up. A string of small sales or gigs across many months can total more than it seems like in the moment, which is part of why the year-end net profit number is the one that matters, not any single transaction.
The takeaway
A side hustle run by a teenager is subject to the same basic self-employment tax logic as one run by an adult: once net profit clears the applicable threshold, self-employment tax generally applies, and below it, it generally doesn’t. Because the specific dollar threshold and interacting rules around dependency and income tax filing can shift and vary by situation, checking current official guidance or talking with a tax professional is the more reliable path than assuming based on age or the size of the operation.