Between 1971 and 1980, he won an additional nine major championships, overtook Bobby Jones' record of 13 majors, and became the first player to complete double and triple career slams of golf's four professional major championships. When Nicklaus claimed his 18th and final major championship at age 46 at the 1986 Masters, he became the tournament's oldest winner. Nicklaus joined the Senior PGA Tour (now known as the PGA Tour Champions)  when he became eligible in January 1990, and by April 1996 had won 10 tournaments, including eight major championships despite playing a very limited schedule. He continued to play at least some of the four regular Tour majors until 2005, when he made his final appearances at the Masters Tournament and The Open Championship.

Later in 2005, Nicklaus finished his professional career at The Open Championship played at St Andrews on July 15, 2005.[52] On St Andrews, Nicklaus stated:

In 1977, Nicklaus won his 63rd tour event, passing Ben Hogan to take second place on the career wins list, behind only Sam Snead (subsequently Hogan's official career PGA Tour victory total was put at 64, including his  1953 Open Championship which was retroactively deemed an official PGA Tour event). He also became the first player to amass over $3million in official PGA Tour earnings. The year also saw Nicklaus win for the first time his own Memorial Tournament, where he described the victory as the most emotional moment of his entire career, and nearly decided to retire from competitive golf.