He sold more than 616,000 shares at around 590p each. Of these around 216,000 of the shares were granted to Thomas, 54, under Barratt’s executive share option scheme. He also sold 400,000 ordinary shares.
Thomas, who became Barratt chief executive two years ago, still holds more than 1m shares following the sale and has options on 900,000 more.
The move follows disposals by other directors of publicly-listed house builders in the last few weeks triggering fears that major house builders are calling the top of the market.
Berkeley founder Tony Pidgley and chief executive Rob Perrins cashed in shares in the house builder worth more than £40m in the first week of September.
Days later founder of Redrow, Steve Morgan, sold £153m worth of shares held through an investment vehicle and a charitable trust just days after revealling he was stepping back from day to day running of the business to take a non-executive chairman role.