The 22-year-old Frenchman has been a long-term target of the club and has agreed a four-year contract, after passing his medical at the American Express Elite Football Performance Centre earlier today.
Head coach Graham Potter said, “Neal is a talented striker, with good strength and pace, and he is a goalscorer. He will add an extra dimension to our existing forward options, and we are delighted to have completed the transfer.
“The club has been monitoring Neal and has been aware of his ability for some time. Separately I was also aware of his obvious ability at Swansea, and came up against him in the Championship last season.
“His record in the Championship has been exceptional, with 41 goals across the last two seasons, and now his challenge is to transfer that to the Premier League.”
Born in Versailles, Maupay began his career in the Cote D’Azur with Nice, where he made his first-team debut at the age of 16 in 2013. After 44 games for Nice, he moved to St Etienne at the age of 18.
While with St Etienne, he also spent time on loan with Brest, and made more than 100 appearances in France, most as a teenager. He moved to England in 2017, when he joined Brentford.
Maupay scored 41 goals in two seasons at Griffin Park, making 75 starts and 20 substitute appearances in a total of 95 games for the Bees.
He’s also been capped by France at under-16 to under-21 levels; and last season was voted Brentford’s Supporters’ Player of the Year and Players’ Player of the Year. He also won the 2018/19 EFL Player of the Year at the London Football Awards.