Seller's premium is auction terminology for the percentage fee charged by the house to the consignor of a lot, deducted from the hammer price prior to settlement. In international jewellery and gemstone practice the term is used interchangeably with seller's commission, although technical usage at some houses reserves commission for the deducted percentage and premium for any additional fee structure layered on top. Seller's premium sits opposite buyer's premium — the figure added to the hammer price and paid by the successful bidder — and the two together comprise the principal auction-house revenue on each lot sold.

Published rates

Major-house seller's-premium schedules at Sotheby's, Christie's, Phillips, and Bonhams typically tier by lot value, with lower percentages on high-value consignments and higher percentages on small estate goods. A high-value coloured stone or signed jewel might be consigned at 6 to 10 per cent, while an entry-level estate piece would carry 20 to 25 per cent. The schedules are starting points for negotiation, and meaningful waivers, reductions, or commission-sharing arrangements are common on strategic consignments at the top of the market.

Distinction from buyer's premium

Buyer's premium is added to the hammer price and paid by the purchaser; published rates at the international houses currently run between 25 and 27 per cent on the first tranche of value and step down on higher tranches. Seller's premium is deducted from the hammer price and paid by the consignor. The total auction-house revenue on a lot is the sum of both — frequently 30 per cent or more of the hammer figure when both fees are aggregated, which is why net-realisation modelling is materially different from gross-hammer thinking for consignors.

Ancillary fees

Beyond the headline percentage, consignors are commonly responsible for insurance during the consignment period, illustrated catalogue fees, gemmological-laboratory fees where reports are commissioned, photography, and shipping. These are negotiated alongside the seller's premium and are itemised on the consignment agreement. The cumulative deduction from gross hammer can be material on smaller lots, where flat-rate ancillary fees consume a higher percentage of value.

In the trade

For consignors, the terminology matters less than the substance. Whether the deduction appears on the consignment agreement as commission, premium, or vendor's commission, the question is the same: what is the final figure deducted from hammer, including all ancillary fees, before settlement? A written net-realisation projection at low, mid, and high estimates is the document worth requesting from the specialist before signing. Published schedules at the major houses are starting points; serious consignments are routinely settled at materially better terms than the published rate suggests.

Further reading

• GIA Gems & Gemology — auction-market practice
• ICA — auction terminology and trade commentary
• AGTA — coloured-stone trade glossary