My first side income was small: a few hundred dollars for helping a local business with its social media. I was thrilled. Then a friend casually asked, “Are you setting aside money for taxes?” and my stomach dropped. I had spent it all on groceries and a new set of kitchen storage containers I definitely didn’t need. Nobody had told me that money you earn from home is taxable even if no one sends you a form.

If you’re a stay-at-home mom starting to earn online, taxes may be the least glamorous part of the journey, but understanding the basics can save you from nasty surprises. The rules have also been shifting in recent years, especially around payment app reporting, which has left a lot of people confused.

In this guide, I’ll explain the side hustle tax basics for U.S. moms in plain English: what you owe, which forms you might see, how to plan quarterly payments, and how to keep your records simple. (I’m not a tax professional, and tax rules depend on your situation and where you live. This is general information, so please check with the IRS or a qualified tax preparer before making decisions.)

The Big Idea: All Income Is Taxable

Here’s the key point repeated by tax pros everywhere: side hustle income is taxable from the first dollar, whether or not you receive a 1099 or any other form. If you earn money doing freelance work, selling products, creating content, or earning commissions, it generally counts as self-employment income.

The forms you might see only change how the income gets reported to the IRS, not whether it’s taxable.

The $400 Rule That Catches Most Beginners

This is the number people overlook. If your net earnings from self-employment are $400 or more for the year, you generally:

  • Owe self-employment tax of 15.3% on net earnings, which funds Social Security and Medicare
  • Must file Schedule SE with your tax return
  • Usually report your business income and expenses on Schedule C

This applies whether or not you get any form. Here’s a simple illustration from a tax-resources writer: if your net side hustle earnings were $6,000, the self-employment tax would be roughly $848. Nothing in the mail tells you that amount is due, but it still is. (Self-employment tax is calculated on about 92.35% of net earnings, and you can deduct half of it when figuring your income tax.)

And remember: self-employment tax is in addition to regular federal income tax (and possibly state tax).

Which Tax Forms Might You Get?

Tax forms for side income can feel like alphabet soup. Here’s a plain-English guide:

Form 1099-K (payment apps and marketplaces)

This form comes from platforms that process payments, like PayPal, Venmo, Etsy, Stripe, and Upwork. After a back-and-forth with a lower threshold that was repeatedly delayed, recent federal law restored the long-standing rule: a platform issues a 1099-K only if you receive more than $20,000 in payments and have more than 200 transactions. Most casual sellers won’t reach that level.

Important: If you don’t get a 1099-K, you still must report your income.

Form 1099-NEC (clients who pay you directly)

A business that pays you for services may send you a 1099-NEC. The reporting threshold was long $600, and recent changes reportedly raise it to $2,000 for future years. Tax resources describe the change, but thresholds can be adjusted, so verify the current number with the IRS. Again, whether or not you get this form, the income counts.

Form 1099-MISC, W-2, and others

Some payers use different forms. If you work as an employee for any company, you’ll receive a W-2 instead.

Schedule C and Schedule SE

These aren’t forms you receive. They’re parts of your tax return where you report your business income and expenses (Schedule C) and calculate self-employment tax (Schedule SE).

Quarterly Estimated Taxes: The Penalty Most First-Timers Miss

When you work for an employer, taxes come out of every paycheck. When you’re self-employed, nobody withholds anything, so the IRS expects you to pay during the year.

  • The general rule: If you expect to owe $1,000 or more in federal tax for the year from your side hustle (after subtracting any withholding or credits), you usually need to make quarterly estimated tax payments to avoid an underpayment penalty.
  • A common rule of thumb: Many tax professionals suggest setting aside roughly 25% to 30% of your side hustle earnings for taxes. Your actual share depends on your income, deductions, and tax bracket, so adjust it with a professional.
  • Where to pay: Through the IRS’s online payment tools or by following instructions for the estimated tax payment form. Check due dates on the IRS website.

If your spouse has a job with tax withholding, you might be able to adjust their withholding (on a W-4) to cover some of your side hustle taxes. A tax preparer can help you decide.

What Can You Deduct?

Self-employed people can generally deduct ordinary and necessary business expenses, which reduces the profit you pay tax on. Common examples (check the rules for your situation):

  • Software and subscriptions used for your work
  • Supplies and materials
  • Platform and payment fees
  • Advertising and marketing costs
  • A reasonable share of internet and phone used for the business
  • Equipment such as a laptop, camera, or microphone
  • Courses and training directly related to your business
  • Mileage or travel for business purposes
  • A home office, if you meet the requirements (regular and exclusive use)

Some tax resources also mention a possible qualified business income deduction of up to 20% for certain self-employed people, subject to income limits and other rules. Ask a tax professional whether it applies to you.

Caution: Don’t deduct personal expenses, and keep proof of everything you claim.

Is It a Business or a Hobby?

The IRS looks at whether you operate in a businesslike way and aim to make a profit. A real business keeps records, tracks income and expenses, markets itself, and works to improve profitability. If you’re unsure, talk to a tax professional.

Records: Keep It Simple

Good records make tax time painless. Here’s a simple system:

  1. Open a separate bank account (and debit card) just for your side income and expenses.
  2. Save receipts digitally. Take photos and store them in a folder by month.
  3. Track income as you get paid: date, client or platform, amount.
  4. Track expenses: date, vendor, amount, purpose.
  5. Keep a mileage log if you drive for business.
  6. Review monthly. Spend 20 minutes updating a simple spreadsheet or bookkeeping app.
  7. Move your tax set-aside into a separate savings account each time you get paid.

Pro tip: Treat your set-aside money like it already belongs to the IRS. Don’t spend it.

A Simple Money Flow for Every Payment

Whenever you get paid:

  • 25% to 30% goes to your tax savings account (adjust with a professional’s advice)
  • A portion goes to business expenses and reinvestment
  • The rest is yours to pay yourself and your family

What About Childcare and the Dependent Care Credit?

If you pay for care so you can work, you may be eligible for the child and dependent care credit, and the credit generally requires earned income, which can include self-employment income. The rules have details, so ask a tax professional how your side hustle affects this.

When to Get Help

Consider a tax professional if:

  • You’re not sure whether you need to make quarterly payments
  • Your income is growing quickly
  • You sell across multiple platforms or states
  • You have a spouse with a complicated tax situation
  • You want to set up a business entity or hire help
  • You received a notice from the IRS

Free or low-cost help may be available through IRS-supported volunteer programs if you qualify.

Common Mistakes to Avoid

  • Assuming no 1099 means no tax.
  • Spending the tax money.
  • Mixing personal and business money.
  • Skipping quarterly payments and getting hit with penalties.
  • Not keeping receipts.
  • Forgetting state taxes. States may have their own rules.
  • Ignoring tax notices. Respond promptly.

Your Tax Setup Checklist

  • Open a separate account for my side income
  • Set up a simple income and expense tracker
  • Open a savings account for my tax set-aside
  • Save receipts digitally
  • Check whether I need to pay quarterly estimated taxes
  • Note the 1099 forms I might receive
  • Schedule a quick check-in with a tax preparer

Make Taxes a Small Part of Your Bigger Plan

Taxes are one piece of building a profitable online income. If you’d like a beginner-friendly roadmap for making money online as a stay-at-home mom, take a look at my ebook:

The Stay-At-Home Mom’s Guide To Making Money Online

The Stay-At-Home Mom’s Guide To Making Money Online

Trust me, a little organization up front makes the whole journey calmer.

Final Thoughts

Side hustle taxes feel intimidating, but the basics are simple: income is taxable from the first dollar, net earnings of $400 trigger self-employment tax, many people need to pay quarterly, and good records make everything easier. Set aside money from every payment, keep your finances separate, and get professional help when you need it. A few small habits now will let you enjoy your earnings without dread when tax season comes.