A silent auction is a sealed-bid format where bidders write their bids on paper sheets next to each lot during a defined bidding window (usually 2–4 hours at a fundraising event). At close time, the highest bid on each sheet wins. Increasingly, the paper sheets are replaced by mobile bidding apps.
Silent auctions are the dominant format for charity galas and school fundraisers because they don’t require a licensed auctioneer, don’t disrupt the social flow of an event, and let many lots close simultaneously rather than serially. The trade-off is reduced bidding energy — without a live caller pushing prices up, silent auctions often clear at lower prices than equivalent live auctions of the same lots.
Modern silent auction software has changed the format dramatically. Mobile bidding apps eliminate the bid-sheet bottleneck (where one bidder camps over a popular sheet, blocking others), enable bid notifications (“you’ve been outbid”), and capture buyer information for follow-up donations. The best charity event operators report 20–40% revenue lifts when migrating from paper to mobile bidding. The format remains popular because it scales well to events with 100–500 attendees and 50–300 lots without requiring extensive auctioneer infrastructure.