The online auction, which is in its 15th year, got underway Sunday night with an opening bid of $25,000 but by Monday the bid had reached $350,000. The auction will close on Friday June 6 and the proceeds will benefit the San Francisco-based GLIDE Foundation.
The lunch normally takes place at New York's Smith & Wollensky steakhouse and the winning bidder is allowed to bring seven friends along. The exact date of the lunch is unknown and is decided on by the winner and Buffett.
The winning bid last year was for over $1 million, well below the mark reached in 2012, a record $3.5 million.
Buffett has been at the forefront in getting business leaders to support charitable causes. His initiative, The Giving Pledge, has signed up more than 100 billionaires from around the globe, who have vowed to donate half of their net worth during their lifetime or after their death.