Understanding buyer's premium is one of the most important steps for any jewelry buyer. It directly affects the true cost of the piece you win. This guide breaks down how it works, the different fee and tax structures you will see on lots, and how to calculate your total cost with confidence.
Quick Answer
Buyer's premium is the fee charged by the auction house on top of the hammer price. If you win a lot at $2,000 and the buyer's premium is 25%, you pay $2,500 before taxes, shipping, import duties, or other fees. Watch the wording: "including VAT" means tax is already inside the premium, while "+ VAT" means tax is added on top.
3.Common fee structures
Flat percentage
The same rate applies to the full hammer price.
Tiered premium
Different rates apply to different portions of the hammer price.
Online surcharge
Some houses add an extra fee for bids placed through third-party platforms.
4.How tax is applied: "including" vs "+ tax"
On jewelry lots you will see the premium written in two very different ways, and the wording changes what you actually pay. VAT, GST, and HST are regional sales taxes — VAT in the UK and Europe, GST in Australia, New Zealand and India, and GST/HST in Canada.
When a lot shows "(including VAT)", "(including GST)", or "(including tax)", the tax is already baked into the premium rate. Nothing extra is added on top.
When a lot shows "+ VAT", "+ GST", or "+ HST", the tax is charged separately on the premium, so your total is higher than the headline rate suggests.
Key point
Two lots can both say "17%" and cost you different amounts. On a $1,000 hammer, "17% (including VAT)" adds $170, while "17% + VAT" adds $170 premium plus $34 VAT = $204.
5.What the labels on each lot mean
Here is how the most common buyer’s premium labels you will see on our lots translate into real costs.
6.Buyer’s premium calculator
Enter the hammer price and the premium rate, pick the tax that applies, and choose whether it is included in the premium or added on top. Add an online fee if the lot has one.
VAT
None
VAT
GST
HST
Estimates only. Tax rates are pre-filled with common defaults (VAT 20%, GST 5%, HST 13%) and can be edited. Always confirm the exact terms in the auction house conditions of sale.
7.Example calculation
Take a lot with a "17% + VAT" buyer’s premium and a $4,000 hammer price.
If the same lot were "17% (including VAT)" instead, the tax line would disappear and you would pay only $4,680 — the same headline rate, $136 less in real money.
8.Tips before you bid
- Check the auction house premium rate before bidding
- Read the wording carefully: "including" tax versus "+" tax changes your total
- Watch for extra platform or online bidding fees
- Include shipping, insurance, and import duties in your budget
- Compare total cost across auction houses, not just hammer prices
