James maintained a low-key appearance as dressed down in a navy blue t-shirt which he teamed with a dark grey jacket and sported comfortable trainers.
The musician has largely shunned the limelight but did follow in his famous dad’s footsteps by pursuing music.
He released his debut single Available Light in 2010 before releasing his first album Me in 2013 and his second, The Blackberry Train, in 2016 – each co-produced by his father.
James is the younger brother of Mary McCartney, 52, and Stella McCartney, 50, and is the one son of Sir Paul, 80, and his late wife Linda.
Sir Paul McCartney pictured together with his only son James McCartney
James previously said he had aimed to be “higher than the Beatles”.
“After I got to a certain age, I realised that I used to be somewhat higher than other kids in school at guitar and took pride and delight in that,” he told the BBC in 2012. “I then dreamt of being higher than The Beatles. I’m undecided if I can try this. If anything, I might like to be equal to The Beatles – but even that is quite tough.”