If you sell on Poshmark, the income is almost always taxable, and Poshmark taxes work differently depending on whether you’re emptying your closet, selling as a hobby, or running a resale business. The IRS treats all income as taxable unless a specific rule excludes it, and that applies whether you move five items a year or five hundred, and whether or not Poshmark sends you a tax form. The one common exception is selling your own used clothing or accessories for less than you originally paid, which creates no taxable income at all.
When Your Sales Aren’t Taxable
Selling personal items for less than you paid doesn’t create taxable income. A jacket you bought for $120 and sold for $40 is an $80 loss, not income. Losses on personal-use property aren’t deductible either, so the transaction is essentially invisible to the IRS.
The wrinkle shows up if Poshmark sends you a Form 1099-K that includes those closet-cleanout sales in its gross total. You still have to account for the amount so the IRS can match the form to your return. Report the 1099-K amount on Schedule 1 (Form 1040) and enter an offsetting adjustment on the same form, so the net taxable income from those personal sales is zero.1Internal Revenue Service. Form 1099-K FAQs – Common Situations You can also report the transactions on Form 8949, which flows to Schedule D. Keep records of what you originally paid so you can prove the loss if the IRS questions it.
Hobby or Business? The Classification Changes Everything
Once you’re selling more than your own used items, the IRS wants to know whether you’re running a business or pursuing a hobby. The difference has real money attached.
Business sellers file Schedule C, deduct expenses, and pay self-employment tax on net profit. Hobby sellers report income on Schedule 1, line 8j, and can’t deduct any expenses against it.2Internal Revenue Service. Know the Difference Between a Hobby and a Business That gap is punishing. A hobbyist who grossed $3,000 and spent $2,500 on inventory still owes tax on the full $3,000.
The test is whether your activity is “engaged in for profit” under Internal Revenue Code Section 183.3Office of the Law Revision Counsel. 26 USC 183 – Activities Not Engaged in for Profit The IRS weighs nine factors, including how you keep your books, the time and effort you put in, whether you depend on the income, and your profit history. No single factor decides it.
A useful benchmark: show a profit in at least three of five consecutive years, and the IRS presumes it’s a business unless the agency can prove otherwise.3Office of the Law Revision Counsel. 26 USC 183 – Activities Not Engaged in for Profit You don’t have to wait that long, though. Sellers who source inventory for resale, track expenses, and dedicate regular hours to listing and shipping are generally treated as businesses from the start.4Internal Revenue Service. About Schedule C (Form 1040) – Profit or Loss from Business (Sole Proprietorship)
If your Poshmark activity looks like a side hustle with real sourcing and effort, business classification is almost always better. The deductions outweigh the self-employment tax that comes with them.
What the 1099-K Threshold Actually Means
Poshmark reports your gross sales to the IRS on Form 1099-K when you cross the federal threshold. After several years of proposed changes, that threshold is now $20,000 in gross payments and more than 200 transactions in a calendar year. The “One, Big, Beautiful Bill” retroactively reinstated it, reversing the lower amounts planned under the American Rescue Plan Act.5Internal Revenue Service. IRS Issues FAQs on Form 1099-K Threshold Under the One, Big, Beautiful Bill
The number on your 1099-K is gross: item price, shipping, and sales tax Poshmark collected, with no subtraction for Poshmark’s commission. It will be higher than what hit your bank account. Business sellers use that gross figure as the starting point on Schedule C, then deduct fees, shipping, and other expenses to reach net profit.
Two things trip people up. Some states set their own 1099-K thresholds well below the federal level, so you may get a form even under $20,000. And not getting a 1099-K doesn’t eliminate your tax obligation. The threshold governs the platform’s paperwork, not your duty to report. A seller with $8,000 in profitable sales across 50 transactions still owes tax on the profit, even with no form filed.6Internal Revenue Service. Form 1099-K FAQs
Deductions You Can Take as a Business Seller
The point of filing as a business is deducting ordinary and necessary expenses, which lowers both your income tax and your self-employment tax. A few categories do most of the work for Poshmark sellers.
Cost of Goods Sold
Your largest deduction is almost always what you paid for the items you sold. Buy a dress at a thrift store for $8, sell it on Poshmark for $45, and your cost of goods sold on that transaction is $8. Only items actually sold during the tax year count; unsold inventory carries into the next year.
If you buy a bulk lot and sell only part of it, allocate a reasonable cost to each piece. If you’re selling items from your own closet through the business, document what you originally paid. Without proof of original cost, the IRS may treat your cost as zero and tax the entire sale price.
Platform Fees and Shipping
Poshmark’s commission is fully deductible. The platform takes a flat $2.95 on sales under $15 and 20% on sales of $15 or more.7Poshmark. What Are the Fees for Selling on Poshmark Any shipping cost you pay out of pocket and aren’t reimbursed for is also deductible. Together, these two line items can eat a significant share of your gross revenue, and recovering them through deductions matters.
Supplies and Mileage
Packaging materials, printer ink, hangers, steamers, lighting, and similar supplies used for the business are deductible. So are miles driven to the post office, thrift stores, and estate sales for sourcing. Track mileage contemporaneously with an app or a simple log. Reconstructing it from memory at tax time is the kind of thing that collapses under audit.
Home Office
If you use a dedicated space in your home exclusively and regularly for your Poshmark business, you can claim a home office deduction. “Exclusively” is the operative word. A spare bedroom that doubles as a guest room doesn’t qualify. A corner of your garage used only for photographing, storing inventory, and packing does.8Internal Revenue Service. Publication 587 (2025) – Business Use of Your Home
The simplified method lets you deduct $5 per square foot up to 300 square feet, capped at $1,500.8Internal Revenue Service. Publication 587 (2025) – Business Use of Your Home The regular method calculates the actual percentage of home expenses (rent, utilities, insurance) tied to the business space. The simplified method is usually enough unless you have a large dedicated area.
One exception to exclusive use is worth knowing. If you store inventory or product samples in your home, you can deduct that storage space even if it isn’t used only for business, as long as your home is the only fixed location of your business.8Internal Revenue Service. Publication 587 (2025) – Business Use of Your Home
Self-Employment Tax
Business sellers owe self-employment tax on net profit of $400 or more. This covers Social Security and Medicare contributions that would normally be split between an employee and employer. You’re both, so you pay both halves: 15.3% total, broken down as 12.4% for Social Security and 2.9% for Medicare.9Internal Revenue Service. Self-Employment Tax (Social Security and Medicare Taxes) The Social Security portion applies only to net earnings up to $184,500 in 2026.10Social Security Administration. Contribution and Benefit Base Medicare has no cap.
You calculate the tax on Schedule SE using the net profit from Schedule C. A small consolation: you can deduct half of your self-employment tax when figuring your adjusted gross income, which lowers your income tax.9Internal Revenue Service. Self-Employment Tax (Social Security and Medicare Taxes)
Quarterly Estimated Payments
Nobody withholds taxes from self-employment income. If you expect to owe $1,000 or more in combined income tax and self-employment tax, you’re required to make estimated quarterly payments.11Internal Revenue Service. Estimated Taxes They cover the tax as you earn it instead of leaving one enormous bill in April.
The 2026 deadlines:
- April 15, 2026, for income earned January through March
- June 15, 2026, for income earned April through May
- September 15, 2026, for income earned June through August
- January 15, 2027, for income earned September through December
Submit payments on Form 1040-ES by mail, through IRS Direct Pay, or via the IRS2Go app.11Internal Revenue Service. Estimated Taxes
Miss payments or underpay, and the IRS charges an underpayment penalty. You can avoid it by paying at least 90% of the current year’s total tax or 100% of the prior year’s tax, whichever is smaller. If your adjusted gross income exceeded $150,000 last year, the second option rises to 110%.12Internal Revenue Service. Underpayment of Estimated Tax by Individuals Penalty In your first profitable year, basing estimates on projected current-year earnings is the safer approach, since there’s no prior-year liability to fall back on.
The 20% Qualified Business Income Deduction
Business sellers on Schedule C may also qualify for a 20% deduction on their qualified business income under Section 199A. It applies to pass-through businesses like sole proprietorships and can meaningfully lower your tax bill.13Office of the Law Revision Counsel. 26 U.S. Code 199A – Qualified Business Income
Clothing resale isn’t a “specified service trade or business” (the category that includes law, consulting, and financial services), so it qualifies regardless of income. If your taxable income before the deduction is below $201,750 for most filers, or $403,500 for married couples filing jointly in 2026, the math is simple: deduct 20% of your net business income or 20% of your taxable income, whichever is less.
If Schedule C shows $15,000 in net profit and you’re under the threshold, you exclude $3,000 from taxable income. It doesn’t reduce self-employment tax, only income tax, but plenty of Poshmark sellers miss it entirely.
Records That Actually Hold Up
The IRS requires documentation supporting every item of income, deduction, or credit on your return.14Internal Revenue Service. What Kind of Records Should I Keep For a Poshmark business, that means purchase receipts for inventory (register tapes, credit card statements, or bank records showing payee, amount, date, and description), Poshmark sales records from your seller dashboard showing each sale with commission and shipping, expense documentation for packaging, mileage, and home office, and an inventory log of what you bought, sold, and still have at year-end.
Sourcing from garage sales, estate sales, and flea markets rarely comes with formal receipts. When one isn’t available, write a contemporaneous log entry noting date, location, items, and amount paid. Pairing supporting documents, like a bank withdrawal near the date alongside your handwritten log, strengthens your position.15Internal Revenue Service. Burden of Proof A spreadsheet reconstructed months later carries much less weight than a note written the day of.
Keep tax records for at least three years from the date you file. Underreport income by more than 25% of your gross and the IRS has six years. Never file a return and there’s no time limit at all.16Internal Revenue Service. How Long Should I Keep Records
Penalties for Not Reporting
Skipping Poshmark income doesn’t just mean a bigger tax bill later. Miss the filing deadline, and the IRS charges a failure-to-file penalty of 5% of unpaid tax for each month or partial month the return is late, up to 25%.17Internal Revenue Service. Failure to File Penalty A separate failure-to-pay penalty of 0.5% per month runs alongside it if you owe and haven’t paid. Interest accrues on top of both, currently 7% annually for the first quarter of 2026 and 6% for the second.18Internal Revenue Service. Quarterly Interest Rates
Certain patterns raise audit risk. Reporting net losses year after year invites scrutiny under hobby-loss rules. Claiming 100% business use of a vehicle, using rounded numbers instead of exact figures, and sudden spikes in deductions compared with prior years are known triggers. Heavy cash purchases demand particularly careful documentation, since cash transactions are harder for the IRS to verify.
State Sales Tax Isn’t Your Problem
Poshmark handles state and local sales tax collection in the vast majority of states. Under marketplace facilitator laws now adopted by nearly every state, the platform is legally responsible for calculating, collecting, and remitting sales tax on transactions made through it. You don’t register for a sales tax permit or file sales tax returns for your Poshmark sales.
That coverage applies only to Poshmark’s platform. Sell through your own website or at in-person events, and you’re on your own for sales tax there. For Poshmark-only sellers, the real focus is accurate reporting of federal income and self-employment tax.