It depends on where you live and what the business does, so check your city and county rules before your kid takes money. Many small kid services fall under the thresholds that trigger registration, and food is the most common exception. One call to your local clerk's office beats an afternoon of searching, and anything you read online, including this, is a starting point rather than a ruling.
This is the question where being confidently wrong costs you the most, so treat everything below as a place to start rather than an answer.
Rules vary by state, county, and city, and they usually turn on what the business does rather than how old the owner is. A kid raking leaves for neighbors and a kid selling cupcakes at a farmers market are in two different categories, even at the same age.
Food is the most common place families run into real requirements. Most states have some version of a cottage food rule governing what can be made in a home kitchen and sold, and those rules differ on what foods qualify, whether you need to register, and where you are allowed to sell. If your kid's idea involves food, look that up specifically for your state before anyone takes money.
For everything else, one call to your city or county clerk's office answers it faster than an afternoon of searching. Ask two things: whether a business at this size needs to register, and whether there are rules about a minor doing this kind of work.
If real money starts moving, or your kid hires someone, that is the point to talk to an accountant rather than the internet.
Five questions about age, budget, time, and what they actually like doing. Four matched ideas at the end, free, with no email needed to see them.
Take the quizA kid who cuts, edges, and cleans up usually starts between $25 and $40. Professionals charge about $30 to $85 a visit, and a young founder starting below that is being paid less for being unproven, not for being young.
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What should a kid charge to mow a lawn?Ten people who already know them, one prepared sentence, and an easy way for each of them to say no.
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How does a kid find their first customer?Less than almost anyone expects, and for a lot of these ideas the honest answer is nothing until somebody has already said yes to a price.
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How much money does a kid need to start a business?Earlier than most people think, as long as the business matches what the kid can actually handle. The limit is rarely age itself.
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What age can a kid start a business?A program from Founder's Best Friend. Built for kids 8 to 18 who want something of their own.