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Selling, fees & tax

Buyer's Premium Calculator

The hammer price is not the price. Add the buyer's premium, sales tax on the total, and shipping, and a $1,000 bid regularly settles above $1,250. This works backwards from what you are willing to spend to the number you should actually bid.

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Leave at 0 to work backwards from your budget.

—the highest you should bid

How a bid becomes a total.
LineAmountShare of total

The gap between the bid and the invoice

A 20% premium and 7% sales tax turn a $1,000 hammer into roughly $1,284 before shipping. Bidders who work from the hammer figure routinely overspend by a quarter, and the moment it happens is in the last thirty seconds of a lot, when there is no time to do the sum.

total = hammer × (1 + premium) × (1 + tax) + shipping max bid = (budget − shipping) ÷ ((1 + premium) × (1 + tax))

Details that move the number

  • What tax applies to. Most houses charge tax on hammer plus premium; some include shipping. The difference on a four-figure lot is real money.
  • Premium tiers. Several houses reduce the premium above a threshold, so the effective rate on a large lot is lower than the headline.
  • Card-not-present surcharges. Paying by card rather than transfer adds up to 3% at some houses.
  • eBay has none of this — the bid is what you pay, plus tax and postage. It is why the same card often hammers higher there.

Questions people ask about this

What is a buyer's premium?

A percentage the auction house adds to the winning bid, paid by the buyer on top of the hammer price. In card auctions it typically runs 15–20%. It is how the house earns from a sale where the seller pays little or no commission, and it means the invoice always exceeds the bid.

How much should I bid to stay in budget?

Divide your all-in budget, less shipping, by (1 + premium) × (1 + tax). At a $1,000 budget with a 20% premium and 7% tax and $25 shipping, the highest safe bid is about $760 — not $1,000, and not $833.

Is sales tax charged on the buyer's premium?

At most houses, yes — tax is calculated on the hammer plus the premium, and some include shipping in the taxable base too. It is worth checking the specific house's terms, because on a four-figure lot the difference between the two treatments is tens of dollars.

Where these numbers come from

Rates on this page were last checked against the published price lists on . Grading companies change fees and pause tiers without notice — confirm the total on the submission form before you pay.