(Reuters) - Chipotle Mexican Grill ( CMG ) said on Tuesday its board had approved a 50-for-1 split of its common stock, sending the burrito chain's shares about 7% higher in extended trading.

The California-based company said the stock split was subject to shareholder approval at its upcoming annual meeting on June 6. If approved, shareholders of record as of June 18 will get 49 additional shares for each share held.

The shares are expected to begin trading on a post-split basis at market open on June 26, in what the company described would be one of the biggest stock splits in New York Stock Exchange (NYSE) history.

Its shares had closed at a record high of $2,797.56 on Tuesday and had gained more than 70% over the last 12 months.

Chipotle shares have steadily risen after the company topped market estimates for quarterly profit and sales in February, helped by its relatively wealthy clientele ordering its burritos and rice bowls despite menu items getting pricier.

(Reporting by Ananya Mariam Rajesh in Bengaluru; Editing by Devika Syamnath)