Auction Seller Commission Calculator: The Auction House's Cut
Work out the seller's commission an auction house takes from the hammer price — and the net proceeds you actually receive — so you know what selling at auction really nets before you consign.
Adjust the inputs and select Calculate for a full breakdown.
Compare Common Scenarios
How the numbers shift across typical situations for this calculator:
| Scenario | Seller's commission | Your net proceeds |
|---|---|---|
| 15% of $8,000 ($1,200) | 1,200 | 6,800 |
| 10% of $50,000 (high-value) | 5,000 | 45,000 |
| 20% of $2,000 | 400 | 1,600 |
| 25% of $500 (small lot) | 125 | 375 |
How This Calculator Works
Enter the seller's commission rate and the hammer price (the winning bid). The calculator returns the commission the auction house keeps and your net proceeds. Note this is the seller's side only — buyers separately pay a buyer's premium on top of the hammer price.
The Formula
Percentage of an Amount
Amount is the base value, Percentage is the rate applied to it
Worked Example
A 15% seller's commission on an $8,000 hammer price is $1,200, leaving $6,800 before any other deductions. Auction houses make money from both sides: the seller pays a vendor's commission (often 10%–25%) and the buyer pays a buyer's premium on top of the hammer price. So on that same $8,000 lot, the buyer might pay $9,600 total while you receive $6,800 — the house captures the spread. Commission rates are often negotiable, especially for valuable or desirable lots the house wants to win.
Key Insight
Selling at auction means the house earns from both ends, so the spread between what the buyer pays and what you receive can be large. Beyond the headline seller's commission, watch for extra fees that quietly reduce your net: photography and cataloguing charges, insurance while the lot is in their care, a minimum or unsold-lot fee if it doesn't sell, and sometimes a charge for reserve protection. Two levers work in your favor: commission rates are negotiable, particularly for high-value or sought-after items (houses compete to win good consignments), and you can compare houses, since rates and fee structures vary widely. Also weigh the reserve — too high and the lot goes unsold (often still incurring a fee), too low and it may sell below value. Run the net proceeds after commission and all fees against what you'd get selling privately or through a dealer before deciding auction is the best route.
Frequently Asked Questions
How is the auction seller commission calculated?
Multiply the hammer price by the seller's commission rate. A 15% commission on an $8,000 hammer price is $1,200, leaving $6,800 before any other fees.
What's the difference between seller's commission and buyer's premium?
The seller's commission (vendor's commission) is deducted from your proceeds as the consignor. The buyer's premium is added on top of the hammer price for the winning bidder. The auction house earns both, so on one lot it collects from buyer and seller alike.
What's a typical seller's commission?
Often 10% to 25% of the hammer price, varying by house, lot value, and category. Rates are frequently negotiable — high-value or highly desirable lots can command much lower seller's commissions because houses compete to win the consignment.
Are there other fees beyond commission?
Often yes: photography and cataloguing, insurance while in the house's care, an unsold-lot or minimum fee if it doesn't sell, and sometimes reserve or marketing charges. These reduce your net beyond the headline commission, so ask for a full fee schedule before consigning.
Is selling at auction worth it?
It depends on the item and the net after all fees. Auctions reach motivated buyers and can exceed expectations for rare or in-demand lots, but the combined seller's commission and fees take a real cut. Compare your net proceeds against a private sale or dealer offer before deciding.
Related Calculators
Methodology & Review
The commission is the seller's-commission percentage applied to the hammer price; the remainder is the seller's net before other deductions. It models the headline commission only and does not include separate listing, photography, insurance, or unsold-lot fees that some houses charge.
Written by Ugo Candido · Last updated May 22, 2026.