Yes, auction houses do report sales to the IRS, but only when specific thresholds are crossed. An auction platform that processes payments between buyers and sellers files Form 1099-K for a seller once gross proceeds exceed $20,000 and the seller has more than 200 transactions in a calendar year. Separately, any auction house that receives more than $10,000 in cash from a single buyer must file Form 8300 with the IRS and FinCEN. And whether or not a form ever gets filed, you owe tax on any gain from what you sold.
When a 1099-K Gets Filed
The reporting threshold for online auction platforms and other third-party settlement organizations changed on July 4, 2025, when the One, Big, Beautiful Bill was signed into law. That legislation retroactively reinstated the pre-2021 threshold: no 1099-K is required unless gross payments to a seller exceed $20,000 and the total number of transactions exceeds 200 in the same calendar year. Both conditions have to be met.1Internal Revenue Service. IRS Issues FAQs on Form 1099-K Threshold Under the One, Big, Beautiful Bill
This wiped out a phased reduction that had been underway. The IRS had planned to drop the threshold from $5,000 for 2024 to $2,500 for 2025, and eventually to $600, but none of those lower thresholds survived. The $20,000-and-200-transaction rule now applies retroactively, so sellers who received 1099-Ks under the transitional numbers may need to reconcile those forms on their returns.2Internal Revenue Service. Form 1099-K FAQs
One category didn’t change. When a buyer pays by credit or debit card, the payment card processor must report those transactions on Form 1099-K regardless of amount or count. There is no minimum for payment card transactions.3Internal Revenue Service. Understanding Your Form 1099-K
When an Auction House Files Form 8300
An auction house that receives more than $10,000 in cash from a single buyer, whether in one lump sum or in related payments that cross that threshold within a 12-month period, must file Form 8300 with both the IRS and the Financial Crimes Enforcement Network. The rule applies to any trade or business and operates independently of the 1099-K threshold. It covers actual currency, and in many cases cashier’s checks and money orders as well.4Internal Revenue Service. Form 8300 and Reporting Cash Payments of Over $10,000
The auction house has 15 days from receipt to file. Since January 1, 2024, businesses already required to e-file other information returns must e-file Form 8300 too.4Internal Revenue Service. Form 8300 and Reporting Cash Payments of Over $10,000
What the 1099-K Actually Shows
A Form 1099-K lists the seller’s name, address, taxpayer identification number, and the gross amount of all reportable transactions. Gross means the full sale price. Auction fees, commissions, shipping, refunds, and your original cost are not subtracted.3Internal Revenue Service. Understanding Your Form 1099-K
This catches people out. Say you consigned a painting that sold for $12,000 and the auction house kept a 25% commission. You pocketed $9,000, but the 1099-K reports $12,000. If you originally paid $8,000 for the painting, your actual taxable gain is $1,000 once you subtract basis and commission. The records you keep of what you paid and what fees were withheld are what close the gap between the gross figure the IRS receives and the net gain you owe tax on.
What to Do if a 1099-K Is Wrong
If a 1099-K shows the wrong amount, includes transactions that weren’t yours, or shouldn’t have been issued in the first place, contact the issuer right away. The issuer’s name and phone number appear in the upper left corner of the form. Save copies of everything you send.5Internal Revenue Service. Actions to Take if a Form 1099-K Is Received in Error or With Incorrect Information
If you can’t get a corrected form before filing, report the erroneous amount on Schedule 1 (Form 1040), Line 8z as “Other Income — Form 1099-K Received in Error,” then enter an identical offsetting amount on Line 24z as “Other Adjustments — Form 1099-K Received in Error.” The two entries cancel out, and the IRS can see you didn’t ignore the form. The same approach handles personal items sold at a loss: report the gross on Line 8z, offset it on Line 24z.5Internal Revenue Service. Actions to Take if a Form 1099-K Is Received in Error or With Incorrect Information
Backup Withholding
If you don’t give the auction house a valid taxpayer identification number, or you provide one that’s obviously wrong, the auction house has to withhold 24% of your proceeds and send it to the IRS. This is backup withholding. It functions as a prepayment of tax rather than a penalty, and you claim credit for the withheld amount when you file.6Internal Revenue Service. Publication 7951 – Backup Withholding Due to Missing Payee TIN
How Auction Gains Are Taxed
You owe tax on auction gains regardless of whether a 1099-K arrives. What you owe depends on what you sold, how long you owned it, and whether you were selling personal items or running a business.
Figuring the Gain
Your taxable gain is the sale price, minus selling expenses like commission, minus your basis in the item. Basis is generally what you paid, plus the cost of any restoration or improvement. Sell a desk you bought for $400 at a hammer price of $1,200 with a $180 commission, and your gain is $620.
Holding Period and Rate
Hold an item for more than a year before selling and any gain is long-term; one year or less is short-term. You count from the day after you acquired the item through the day you sold it.7Internal Revenue Service. Topic No. 409, Capital Gains and Losses
Short-term gains are taxed at your ordinary income rate. Long-term gains on most assets fall into the 0%, 15%, or 20% brackets. Collectibles are the exception. Long-term gains on art, antiques, rugs, gems, stamps, coins, and precious metals are taxed at a maximum rate of 28%, higher than the usual long-term capital gains rates.7Internal Revenue Service. Topic No. 409, Capital Gains and Losses
Personal-Use Items
Gains from selling personal-use property are taxable. Losses aren’t deductible. Sell a piece of furniture at a profit and you owe tax on the gain. Sell it at a loss and you can’t use that loss to offset other income.8Internal Revenue Service. Capital Gains, Losses, and Sale of Home
Report capital gains and losses from auction sales on Form 8949, which feeds into Schedule D.9Internal Revenue Service. Instructions for Form 8949
Inherited and Gifted Items Have Different Basis Rules
Plenty of auction sellers are disposing of inherited property or something they were given, and the basis math there works differently.
Inherited Property
When you inherit, your basis is generally the item’s fair market value on the date the original owner died, not what they paid for it. This is the “stepped-up basis” (or stepped-down, if value fell). If your grandmother bought a painting for $500 in 1970 and it was worth $15,000 when she died, your basis is $15,000. Sell it at auction for $16,000 and your taxable gain is only $1,000.10Internal Revenue Service. Publication 551 – Basis of Assets
Inherited property is also treated as long-term automatically, no matter how briefly you owned it before selling. Long-term rates apply even if you sell within weeks of inheriting.
Gifted Property
If someone gave you the item during their lifetime, your basis is generally the donor’s adjusted basis, meaning what they paid plus improvements. A special rule kicks in when the fair market value at the time of the gift was lower than the donor’s basis: you use fair market value to calculate a loss but the donor’s basis to calculate a gain. Sell for a price that lands between those two figures and you have neither a gain nor a loss.10Internal Revenue Service. Publication 551 – Basis of Assets
The dual-basis rule matters more than people expect. If you can’t document what the donor originally paid, establishing basis is hard, and you risk the IRS treating the full sale price as gain.
Hobby Sellers vs. Business Sellers
The IRS distinguishes between selling as a hobby and operating a business. The distinction controls whether you can deduct expenses like auction fees, travel to estate sales, storage, and restoration against your auction income.
Treated as a business, you report income and deduct related expenses on Schedule C. Treated as a hobby, you report income on Schedule 1 and cannot deduct expenses against it. Hobby-related deductions were eliminated for tax years 2018 through 2025 by the Tax Cuts and Jobs Act, and even outside that window, hobby expenses are sharply limited under IRC Section 183.11Office of the Law Revision Counsel. 26 U.S. Code 183 – Activities Not Engaged in for Profit
The IRS weighs several factors when deciding: whether you keep business-like records, the time and effort you put in, whether you depend on the income to live, whether you’ve changed methods to try to improve profitability, and whether the activity has actually made money in past years. As a rough guide, an activity that shows a profit in at least three of five consecutive years is generally presumed to be a business.12Internal Revenue Service. Here’s How to Tell the Difference Between a Hobby and a Business for Tax Purposes
For someone liquidating a personal collection or an estate, hobby treatment usually applies. Fine for a one-time event, but if you’re regularly buying items to resell at auction, the IRS will expect business reporting.
Foreign Sellers Are on a Different Track
If you’re not a U.S. person, the 1099-K framework doesn’t apply to you. U.S.-source income paid to a foreign person is generally subject to 30% withholding, though a tax treaty between your country of residence and the United States may reduce or eliminate that rate.13Internal Revenue Service. Publication 515 – Withholding of Tax on Nonresident Aliens and Foreign Entities
To establish foreign status and claim treaty benefits, provide the auction house with Form W-8BEN.14Internal Revenue Service. Instructions for Form W-8BEN The auction house reports the income and any withheld amounts on Form 1042-S rather than on a 1099-K.15Internal Revenue Service. About Form 1042-S, Foreign Person’s U.S. Source Income Subject to Withholding
Penalties for Leaving Auction Income Off Your Return
If you omit auction income, especially income already reported on a 1099-K or Form 8300, the IRS’s matching program will flag the discrepancy between what was reported to it and what you reported on your return.
The accuracy-related penalty is 20% of any underpayment caused by negligence or a substantial understatement of tax. For individuals, a substantial understatement exists when you understate your tax by the greater of 10% of the correct tax or $5,000. Failing to include income shown on a 1099-K is one of the examples the IRS lists as negligence.16Internal Revenue Service. Accuracy-Related Penalty
Interest accrues on top of the penalty from the return’s original due date. The simplest defense is to report all auction income, whether or not a form was issued, and hold on to documentation of your basis so you can prove the correct gain if the IRS asks.