Buyer's Premium Calculator
What the buyer pays, and what the seller keeps.
In 2026 Christie's and Sotheby's charge buyers 28% of the hammer price up to $2 million, Phillips 29%, and Bonhams 30% on the first $35,000 from 1 October 2026, with lower rates on higher bands and tax charged on the premium. The seller pays a negotiated commission out of the same hammer. At a 28% premium, 12% commission and 20% VAT, a £10,000 hammer costs the buyer £13,360 and leaves the seller £8,560.
Figures reviewed September 2026
£13,360
on a £10,000 hammer
The sale itself takes 48.0% of the hammer price.
Rates differ by house, by sale and by band, and some lots carry additional charges. Read the conditions of sale for the figures that will actually apply.
Buyer's premium: what a hammer price really costs
The hammer price is not the price. On top of it the buyer pays a buyer's premium to the auction house, and sales tax or VAT is charged on that premium. At the same time the seller pays a commission out of the same hammer figure. Both sides pay the house, which is why the gap between what a lot cost and what its owner received is always larger than people expect.
This calculator shows both ends of that transaction at once: the buyer's total, the seller's net, and the share of the hammer price the sale itself consumed.
How premiums are structured
Major houses charge a tiered buyer's premium: a higher rate on the first band of the hammer price, then lower rates on the amounts above successive thresholds. In 2026 the first band at the international houses is 28 to 30 percent — 28 at Christie's and Sotheby's up to $2 million, 29 at Phillips, 30 at Bonhams on the first $35,000 from October — stepping to about 22 percent and then to 14 or 15 percent on multi-million dollar lots. Regional and online salerooms often charge a flat rate instead, and online bidding platforms may add a further fee of a few percent.
Rates change, and they differ by sale and by category. The conditions of sale for the specific auction are the only authority; use them for the figures you enter above.
What the seller actually receives
A seller's commission is negotiated, and on desirable property it can fall to zero — occasionally below zero, where a house offers an enhanced hammer share to win a consignment. Against that, deduct the charges that appear on a settlement statement: photography, cataloguing, framing, insurance while in the house's care, shipping, and unsold-lot fees if it does not sell.
Add them all up before you consign. A lot that hammers at $10,000 does not put $10,000 anywhere near your account.
Bidding to a budget, not to a hammer
Work backwards. Decide the total you are willing to pay, then divide by one plus the premium rate and the tax on it. That is your maximum bid. Bidders who set their limit on the hammer price alone routinely overshoot their budget by a quarter.
At a 28 percent premium with 20 percent VAT on it, the divisor is 1.336: a £20,000 all-in budget is a £14,970 maximum bid.
How a tiered premium is actually charged
A tiered premium is charged like income tax, not like a price band. The top rate applies only to the part of the hammer price inside its band; the lower rates apply to the parts above each threshold. A lot hammering just over a threshold therefore pays the lower rate only on the slice above it, and the effective rate on the whole lot is a blend that falls gradually as the price rises.
That is why a flat percentage overstates the premium on an expensive lot and is exact on a modest one. For anything below the first threshold — which covers most lots offered — the flat figure in this calculator is the figure you will pay.
Online salerooms and platform fees
Regional and online auctions often charge a flat premium somewhere in the twenties, and bidding through a third-party platform can add a further three to five percent on top. Read the platform's terms as well as the saleroom's: the two fees are charged separately and both are subject to tax.
| House | First tier | Middle tiers | Top tier | In force from |
|---|---|---|---|---|
| Christie's | 28% up to $2m (£1.5m) | 22% to $8m (£6m) | 15% above | 1 September 2026 |
| Sotheby's | 28% up to $2m (£1.5m) | 22% to $8m | 15% above | 13 February 2026 |
| Phillips, New York | 29% up to $2m | 22% to $8m | 15% above | 12 April 2026 |
| Phillips, priority bid | 25% up to $2m | 20% to $8m | 14% above | Binding bid 48 hours before the sale |
| Bonhams, US | 30% on the first $35,000 | 28% to $750,000 · 25% to $1.5m · 21% to $7.5m | 14% above | 1 October 2026 |
| Bonhams, US, until 30 September | 28% on the first $50,000 | 27% to $1m · 21% to $6m | 14.5% above | Previous schedule |
Each rate applies only to the slice of the hammer price inside its band, and tax is charged on the premium. Wine, cars, coins and some online sales have their own schedules; the conditions of sale for the auction are the authority.
| Hammer price | Buyer pays | Seller receives | Taken by the sale |
|---|---|---|---|
| £1,000 | £1,336 | £856 | 48.0% of hammer |
| £10,000 | £13,360 | £8,560 | 48.0% of hammer |
| £50,000 | £66,800 | £42,800 | 48.0% of hammer |
| £250,000 | £334,000 | £214,000 | 48.0% of hammer |
Flat rates for illustration; the percentages work the same in dollars or euros. The major houses tier the premium, so real totals on large lots are somewhat lower, and US sales tax is charged differently from UK and EU VAT.
Questions we are asked
- What is a buyer's premium?
- A commission the auction house charges the buyer on top of the hammer price. It is usually tiered, and sales tax or VAT is charged on the premium itself.
- How much is the buyer's premium at auction?
- At the major international houses it is 28–30% on the first band in 2026 — 28% at Christie's and Sotheby's up to $2 million, 29% at Phillips, 30% at Bonhams on the first $35,000 from October — stepping to about 22% and then 14–15%. Smaller and online salerooms often use a flat rate, sometimes plus a platform fee.
- Do sellers pay commission too?
- Yes, on the same hammer price, plus charges for photography, cataloguing, insurance and shipping. Commission is negotiable on property a house wants.
- How do I calculate my maximum auction bid?
- Take your total budget and divide it by one plus the premium rate plus tax on the premium. Bid to that hammer figure, not to your budget.
- What is Christie's buyer's premium in 2026?
- From 1 September 2026, 28% of the hammer price up to $2 million (£1.5 million), 22% of the part up to $8 million (£6 million), and 15% above that — the same first tier Sotheby's adopted in February 2026.
- Which auction house has the lowest buyer's premium?
- Among the four major international houses in 2026, Christie's and Sotheby's charge the lowest first tier at 28%. Phillips charges 29%, or 25% with a priority bid placed 48 hours ahead, and Bonhams 30% on the first $35,000 from October 2026.
- How much of a hammer price does the seller keep?
- At a 12% commission with 20% VAT on it, 85.6% of the hammer before any other charges — £8,560 on a £10,000 lot. Photography, insurance, shipping and cataloguing charges come off that figure, and commission is negotiable on property a house wants.
Before You BidRead the lot first
What a piece appears to be, before what is asked for it — photograph the work and start from a figure of your own.