U.S. Open playoff format, explained: Extra holes rules for 2023 & how tiebreaker works in golf

There can only be one.

Four days, four rounds and 72 holes of the U.S. Open may not be enough to declare a winner this year. That means for the first time since 2008 and the 34th time overall, the U.S. Open may be decided by a playoff at the Los Angeles Country Club.

After a first round that saw some record-low scores by Xander Schauffele and Rickie Fowler, the 2023 U.S. Open has settled into a more U.S. Open-like groove, with Tom Kim posting the low round in Round 3 with a four-under 66.

Co-leader Fowler went even in Round 3, this coming after his 18th hole bogey cost him the outright, 54-hole lead entering Sunday. Wyndham Clark capitalized on 18, earning a birdie on the hole that gave himself a share of the lead.

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Here's what you need to know about the U.S. Open playoff format and how a winner could potentially be decided by playoff at the 123rd U.S. Open:

U.S. Open playoff format 2023

Since 2018, the U.S. Open has adopted a new format for playoffs: The players who are tied head to a two-hole playoff, where the winner is decided on aggregate score. If the players are tied beyond the two holes, then sudden-death rules are applied.

Example: If one player shoots even for two holes, but the other player (or players) shoot a +2, then the player who shot for par will win the tournament.

The U.S. Open was the last of the four major tournaments to adopt a non-playoff round format. The Masters changed to sudden death in 1977, the PGA Championship would ultimately settle on a three-hole aggregate and the Open Championship features a four-hole aggregate. 

How extra holes work in golf

Depending on the tournament, there are typically two different types of extra holes and playoff formats.

— Aggregate: Less common, select holes are picked after 72 holes have concluded. Some tournaments have two hole aggregate score, while others have three. Some golf major tournaments use this format, including the PGA Championship, U.S. Open and Open Championship.

— Sudden death: PGA Tour events feature a sudden death format — first player to win a hole, wins. The holes are decided depending on the tournament.

U.S. Open playoff rule change

Former USGA CEO Mike Davis explained the decision to change the format from a full, playoff round to the aggregate format in 2018.

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"There was a time when they (playoff rounds) did make sense before television, before the modern era of wanting everything decided immediately," he said. "There is no correct way to determine a tie in stroke play. … I won't say it was everybody, but seemingly it was, 'Why do we have to come back tomorrow?'"

Essentially, some felt that an extra round was too grueling or non-essential, instead with 

Prior to 2018, a playoff round between tied golfers would take place on Monday. If the score was still tied after the playoff round, then sudden death was introduced. Prior to the introduction of sudden death in the 1950s, an extra playoff round would be played.

Last U.S. Open playoff

The last playoff in the U.S. Open came in 2008, when Tiger Woods and Rocco Mediate went to a Monday playoff round at Torrey Pines. The two tied after the playoff round, with Woods eventually taking the win in sudden death.

Woods took the sudden-death win at Hole 7, after Mediate bogeyed the try. Woods took the win and the $1,350,000 paycheck for the victory.

U.S. Open playoff history

Here's the complete history of playoff wins at the U.S. Open over the event's history, dating back to