The deal was confirmed by the West Midlands club on their Twitter account:
West Bromwich Albionud83dudcf7 Here you go... Welcome to the Baggies, @KieranGibbs! #WBA https://t.co/NOSXkJHVfp
2017-8-30 10:45:16
In a bulletin on their website, the Baggies revealed Gibbs has agreed a four-year deal at the Hawthorns and will wear the No. 3 shirt.
Gibbs posted the following message on his own account:
The 27-year-old leaves Arsenal having spent 13 years at the football club. Gibbs joined the Gunners youth setup in 2004, before going on to battle for the left-back slot in the senior side.