The speaker has to vacate his office in case of following instances:

a. If he ceases to be a member of the Lok Sabha.

b. If he resigns by writing to the Deputy Speaker.

c. If he is removed by a resolution passed by a majority of all members of the Lok Sabha. When such a resolution is under consideration, he cannot preside at the sitting though he may be present. However, he can speak and take part in the proceedings and vote in the first instance (though not in case of equality of votes)

Whenever the Lok Sabha is dissolved, the Speaker does not vacate his office and continues till the newly elected Lok Sabha meets.