Chairman Jeremy Peace said the club would add an extra 3,500 seats within the next three years.
Expansion plans have not yet been finalised but it is believed the Baggies aim to extend the West Stand to expand the ground from its current capacity of around 26,500.
Peace said: “Our medium-long-term plans include the extension of the Hawthorns to around a 30,000-seat capacity within the next three years regardless of divisional status.
“Despite the apparent financial insanity of such a move, we believe it is the right thing to do as we endeavour to move the club forward and pro-actively encourage the next generation of supporters to come to The Hawthorns.”
He added that the pitch will be levelled out this summer and re-laid with a state-of-the-art Desso playing surface, which combines artificial fibres with a natural grass surface.