"He successfully reached the summit this morning guiding a Vietnamese climber," Mingma Sherpa of Seven Summit Treks, his expedition organiser, told AFP.
Nepal is home to eight of the world's 10 highest peaks, including the 8,849-metre (29,032-foot) Everest, and welcomes hundreds of adventurers each spring, when temperatures are warm and winds are typically calm.
Earlier Wednesday, British guide Kenton Cool reached the world's highest point for the 17th time, extending his own record for the most summits by a non-Nepali.
Meanwhile, a 46-year-old Moldovan climber died on the mountain the same day -- the fifth fatality of the season.
Authorities have issued 478 Everest permits to foreign climbers this year, the $11,000 fee part of total costs for a summit ranging from $45,000 to $200,000.
Since most will need a guide, more than 900 people -- a record -- will try to summit this season, which runs until early June.
The 53-year-old Kami Rita Sherpa had held the overall title since 2018, when he ascended Everest for the 22nd time, passing the previous mark he shared with two other Sherpa climbers, both of whom have since retired.
But on Sunday another climber, Pasang Dawa Sherpa, 46, tied the record by reaching the top for the 26th time.
A guide for more than two decades, Kami Rita Sherpa first summited in 1994 when working for a commercial expedition.
Since then, he has climbed Everest almost every year, several times leading the first rope-fixing team to open the route to the top.
"These records were made not with an intention to make them but during my work as a guide," Sherpa told AFP last month as he headed to base camp.
'Everest man'
Dubbed "the Everest man", Sherpa was born in 1970 in Thame, a village in the Himalayas renowned as a breeding ground for successful mountaineers.
Growing up, Sherpa watched his father and then his brother don climbing gear to join expeditions as mountain guides, and was soon following in their footsteps.
In 2019, he reached the summit twice in the span of six days.
Sherpa's client Wednesday was reportedly Chinh Chu, a Vietnamese billionaire who made his fortune in finance, while Cool guided Richard Walker, executive chairman of British supermarket chain Iceland Foods, to the top.
Nepali guides, usually ethnic Sherpas from the valleys around Everest, are considered the backbone of the climbing industry and bear huge risks to carry equipment and food, fix ropes and repair ladders.
Cool, 49, first climbed Everest in 2004, and his 16th ascent last year gave him the sole record for the most summits by a non-Nepali climber, but he told AFP then that he was "surprised" by the attention.
"In reality, it's not that amazing," he said, pointing out that many Sherpa guides had stood on the peak more often than him.
"People go 'it's a world record', it's not a world record," he said. "It's just that I happen to hold the non-Sherpa record, for whatever that is worth, which in my mind, (is) not very much."
The Moldovan climber died at Camp 4, said Expedition Himalaya, which arranged his permit.
"He felt unwell at South Col and despite many attempts to provide him aid he passed away," the company said.
Three Nepali climbers died on the mountain last month when a block of glacial ice fell and swept them into a deep crevasse as they were crossing the treacherous Khumbu icefall as part of a supply mission.
The season's toll rose to four when a 69-year-old US mountaineer died this month during his acclimatisation rotation at around 6,400 metres.