The hammer price is not what you pay at an auction. This calculator adds the buyer’s premium, including tiered rates, any taxes and other costs, and can work out the highest bid that keeps you within your budget.
Auction total cost
How it works
Buyer’s premium = hammer price × premium rate. If the premium is tiered, the first rate applies up to the threshold and the second rate to the part above it. Taxes are then applied to the premium and, if relevant, the hammer price, and other costs are added.
For the highest bid within a budget, the calculator searches for the largest hammer price whose total cost stays at or under your budget.
Worked example
The example uses rupees, but the maths is the same in any currency. Choose yours in the calculator above.
At a hammer price of ₹100,000 with a 20% buyer’s premium and 18% tax on the premium, the premium is ₹20,000, the tax on it is ₹3,600, and the total is ₹123,600, which is 23.6% above the hammer price.
Good to know
- Auction houses set their own premiums and tiers, and rates change. Always read the terms of sale for the specific auction and enter those numbers.
- Tax treatment depends on the country, the item and the seller. The tax fields are left for you to fill in from the auction’s terms or your adviser.
- Import duties, export permits and restrictions on antiques can add cost or rule out a purchase. Check them before bidding on items from abroad.
Frequently asked questions
What is a buyer’s premium?
It is a fee the auction house adds to the hammer price, set as a percentage. It is paid by the buyer on top of the winning bid.
What is a tiered buyer’s premium?
Some auction houses charge one rate up to a certain amount and a lower rate on the part of the price above it. Enter both rates and the threshold.
How do I set a maximum bid?
Enter your total budget. The calculator finds the highest hammer price whose full cost, with premium, tax and other costs, stays within it.