What Is a Buyer's Premium?

If you have ever won an item at auction and then been surprised by the total on your invoice, the buyer's premium is usually the reason. It is one of the most common charges at Ontario auctions, and understanding it before you bid is the simplest way to avoid overpaying. This guide explains what a buyer's premium is, how it is calculated, how it interacts with HST, and how to build it into your bidding.

Key takeaways

• A buyer's premium is a percentage added to the hammer price and paid by the buyer.
• Rates and rules vary by sale, so always read the auctioneer's terms before you register.
• In Ontario, HST is generally charged on the hammer price plus the premium.
• Work backwards from your total budget to set a maximum bid for every lot.

What a buyer's premium is

A buyer's premium is a fee the auction company adds on top of the winning bid, also called the hammer price. It is expressed as a percentage, and it is paid by the buyer, not the seller. Sellers usually pay their own separate commission to the auctioneer, so the buyer's premium is an additional source of revenue that helps the auction company cover advertising, staff, online bidding platforms, payment processing and the cost of running the sale.

Not every auction charges one. Some traditional country and farm sales still run with no premium at all, while most online auctions and many estate and liquidation sales do charge one. The only way to know is to read the terms for that specific sale.

Where to find it

Auctioneers disclose the buyer's premium in the terms and conditions for each sale. Look for it in:

• The sale bill or listing description
• The terms and conditions page on the online bidding platform
• Signs posted at the registration desk at a live sale
• The bidder registration form you sign

On our listings, the terms section often notes the premium, but always confirm with the auctioneer's own terms before you bid. You can browse current sales by area, such as auctions in Toronto or auctions in Huron County, and follow the link to the auctioneer's full terms.

How it is calculated

The premium is calculated on the hammer price. If the premium is 15 percent and you win an item at $200, the premium is $30, so the item costs $230 before tax.

Some auctioneers use different rates depending on how you bid. For example, online bids may carry a higher premium than in-person bids, or a higher rate may apply to lower-priced lots. Some sales cap the premium on very expensive items, such as vehicles or real estate. These variations are all set by the auctioneer, so read the terms line by line.

How HST fits in

In Ontario, HST generally applies to auction purchases. In most cases tax is charged on both the hammer price and the buyer's premium, not just the hammer price. Using the example above, HST would usually be calculated on the $230, not the $200.

There are exceptions, such as certain farm purchases by registered farmers or items sold on behalf of sellers who are not HST registrants, and the rules can be detailed. Do not assume an exemption applies. If you believe one does, ask the auctioneer before the sale what documentation they need, and speak to an accountant if you are unsure.

A worked example

Here is how a simple purchase adds up, using an illustrative 15 percent premium and Ontario's 13 percent HST:

1. Hammer price: $400
2. Buyer's premium at 15 percent: $60
3. Subtotal: $460
4. HST at 13 percent on the subtotal: $59.80
5. Total: $519.80

That is almost 30 percent more than the hammer price. If your budget for the item was $400, you would have needed to stop bidding at roughly $308 to stay within it.

Other fees to watch for

The buyer's premium is the largest add-on, but it is not always the only one. Check the terms for:

• Online bidding or platform fees. Some platforms add a small per-lot or per-invoice fee.
• Credit card surcharges. Some auctioneers add a percentage if you pay by card, or offer a discount for cash or e-transfer.
• Lot or handling fees. Some sales charge a flat amount per lot for handling.
• Shipping and packing. If the auctioneer offers shipping, it is usually extra, and many do not ship at all.
• Storage fees. Items not picked up by the deadline can incur daily storage charges, or may be forfeited.

How to bid with the premium in mind

The easiest habit is to work backwards. Decide the total you are willing to pay, including tax, then calculate the maximum hammer price that fits. A simple formula is:

Maximum bid = total budget ÷ (1 + premium rate) ÷ (1 + tax rate)

With a $500 total budget, a 15 percent premium and 13 percent HST, that works out to about $385. Write that number down next to the lot number before bidding opens.

A few more tips:

• Set limits for every lot, not just the big ones. Small lots add up quickly once fees are applied.
• Use maximum or proxy bids online with the premium already factored in, so you are not tempted to raise your limit in the final seconds.
• Compare like for like. A sale with no premium but higher starting bids may cost the same as one with a premium and lower bidding.
• Ask questions early. If anything in the terms is unclear, call or email the auctioneer before the sale.

Is a buyer's premium fair?

Buyers sometimes feel the premium is a hidden charge, but at a reputable auction it is clearly disclosed in advance. It pays for the services that make the sale possible, including the online platform you bid on, the staff who lot and photograph items, and the payment and pickup arrangements. Experienced bidders simply treat it as part of the price.

What matters is that you know the rate before you bid. If a sale's terms are vague or hard to find, take that as a reason to ask questions or to pass.

Finding auctioneers and their terms

Every auction company sets its own premium and payment rules, and these can change from sale to sale. Our auctioneer directory lists auction companies across the province with links to their websites and bidding pages, where you can review their terms. You can also browse sales by region, such as southwestern Ontario or the GTA and Golden Horseshoe.

Quick checklist

• Find the buyer's premium in the sale terms before you register
• Check whether online and in-person rates differ
• Assume HST applies to the hammer price plus premium unless told otherwise
• Look for card surcharges, platform fees and storage charges
• Calculate your maximum hammer price for each lot in advance
• Ask the auctioneer about anything unclear before bidding

Once the buyer's premium becomes part of your routine calculation, it stops being a surprise and simply becomes one more number to plan around.

Next steps

Ready to put this into practice? Browse the auctioneer directory to review each company's terms, or explore upcoming auctions in the GTA and Golden Horseshoe and southwestern Ontario.