LEXINGTON, Ky. — Keeneland's September Yearling Sale opens Monday with 4,642 racing prospects cataloged for the 83rd edition of the world's premier Thoroughbred auction, which runs through Sept. 26 across 12 sessions.

The sale begins at 1 p.m. ET and will feature Books 1 and 2 during the first four days, cataloging more than 1,100 yearlings representing the auction's highest concentration of sire power, pedigree and physical quality. A Dark Day on Friday, Sept. 18, will break the sale before it resumes Sept. 19.

Last year's September Sale set multiple records, grossing more than $531.7 million for 3,078 horses sold. The auction achieved 56 million-dollar horses, an average price of $172,755 and a median price of $80,000 — all records for the sale. "Buyers from all over the United States and around the world gathered here to propel the auction to its record level, reaffirming the enduring strength of the marketplace," Keeneland President and CEO Shannon Arvin said in a statement.

The 2026 sale will see the debut of the Paddock Building, part of Keeneland's largest capital construction project in history. The three-story structure, which opened to racing fans during the Spring Meet in April, will offer hospitality amenities including the 1936 Room with light food and beverage options, and the Sycamore Room, which will serve full-service lunch by reservation from Sept. 11-20.

Alumni of the September Sale have won 331 stakes worldwide this year through Sept. 10, including 35 Grade 1 events. Recent graduates include Grade 1-winning juveniles Hughes, Miss Monica and Summer Starlet. The 2026 catalog includes siblings to multiple recent graded stakes winners, including half-siblings to Arlington Million winner Burnham Square and Coaching Club American Oaks winner Counting Stars.

Keeneland will livestream the sale at Keeneland.com with online and phone bidding available. Behind-the-scenes sales experience tours are available on selected days from 9-10:30 a.m., offering the Lexington community insight into the auction's operations and economic importance.