Jim "Bones" Mackay is an American professional golf caddie and television golf analyst who has a net worth of $5 million. Mackay is best known for spending 25 years as the caddie for Phil Mickelson, forming one of the longest and most successful player-caddie partnerships in modern professional golf. Mackay was on Mickelson's bag for 41 PGA Tour victories and five major championships.

After Mackay and Mickelson parted ways in 2017, Mackay moved into broadcasting as an on-course reporter for NBC Sports and Golf Channel. He later returned to full-time caddying for Justin Thomas, helping Thomas win the 2022 PGA Championship. Mackay and Thomas separated in 2024, after which Mackay returned to NBC. His combination of decades as an elite caddie and a substantial second career in broadcasting has made him one of the most recognizable non-players in professional golf.

Jim Mackay was born on May 8, 1965, in Redhill, England. His family moved to New Smyrna Beach, Florida, when he was seven years old.

Mackay played college golf at Columbus College in Georgia. After school, he worked in the bag room and pro shop at Green Island Country Club.

His work around the club introduced him to professional golfers and led to opportunities as a caddie.

Before meeting Mickelson, Mackay carried bags for players including Larry Mize, Scott Simpson, and Curtis Strange.

Mackay began working for Phil Mickelson in 1992, at the beginning of Mickelson's professional career.

The partnership lasted 25 years.

Mackay's nickname, "Bones," reportedly came from Fred Couples, who could not remember the tall, thin caddie's name and referred to him by his lanky appearance.

Mackay was alongside Mickelson as the left-hander evolved from an extraordinarily talented player without a major championship into one of the most accomplished golfers of his generation.

Their first major victory came at the 2004 Masters. Mickelson birdied the 18th hole to defeat Ernie Els by one stroke.

Mickelson and Mackay subsequently won the 2005 PGA Championship, the 2006 Masters, the 2010 Masters, and the 2013 Open Championship.

In total, Mackay was on the bag for 41 of Mickelson's PGA Tour victories.

Mackay and Mickelson announced in June 2017 that they were ending their professional relationship.

The split was publicly described as mutual and ended one of golf's best-known partnerships.

Mickelson subsequently employed his brother Tim as his caddie, while Mackay moved almost immediately into broadcasting.

NBC Sports hired Mackay as an on-course reporter in 2017.

His long experience inside the ropes gave him a perspective few television analysts could match. Rather than simply describing swings and scores, Mackay could explain club selection, player-caddie conversations, weather, course management, and pressure from the viewpoint of someone who had spent decades making those decisions alongside one of the world's best golfers.

Mackay worked PGA Tour events, major championships, Ryder Cups, Presidents Cups, and other golf broadcasts for NBC and Golf Channel.

Mackay briefly returned to caddying for Justin Thomas as a substitute before agreeing to become Thomas' full-time caddie in 2021.

The partnership produced a major championship almost immediately.

At the 2022 PGA Championship at Southern Hills, Thomas began the final round seven shots behind the leader but rallied to force a playoff against Will Zalatoris. Thomas won the playoff to capture his second PGA Championship.

Mackay therefore added another major victory to a caddying résumé that already included five with Mickelson.

Thomas and Mackay announced that they were parting ways in April 2024.

After leaving Thomas' bag, Mackay returned to NBC Sports.

NBC immediately placed him back into a prominent on-course reporting role. The network said in 2024 that it expected Mackay to remain part of its golf operation for years to come.

His career has made him unusual even among elite caddies. Mackay spent more than three decades working directly with major-championship golfers while also developing a successful television career capable of continuing long after the physical demands of full-time caddying become less appealing.