Coussaud turned professional in late 2016 and joined the 2017
Alps Tour. He finished runner-up to
Lukas Nemecz at the Gösser Open, and secured his maiden professional win the following week at the Open Golf Clément Ader Paris, where he defeated Spanish amateur
Adri Arnaus on the 5th hole of a playoff, having started the day 9 shots back of the lead. Coussaud finished second on the 2017 Alps Tour Order of Merit, to graduate to the 2018
Challenge Tour. He lost the final of the 2019
Andalucía Costa del Sol Match Play 9 to
Eirik Tage Johansen 2 and 1, and lost a playoff at the 2022
D+D Real Czech Challenge to
Nicolai Kristensen of Denmark. 2023 would be his breakthrough season, where he won
The Challenge in India and recorded a further three runner-up finishes at the
Cape Town Open,
UAE Challenge and
Dormy Open, to finish fourth on the season-long rankings and
graduate to the European Tour. In his rookie season on the
European Tour, he finished runner-up at the 2024
Qatar Masters, a stroke behind
Rikuya Hoshino of Japan. ==Amateur wins==