The Speaker of the Lok Sabha can resign his office by addressing his resignation to

According to Article 94 of the Constitution of India, the Speaker of the Lok Sabha may resign from office by writing under his hand addressed to the Deputy Speaker [1]. Conversely, the Deputy Speaker can resign by addressing the resignation to the Speaker [t3]. This reciprocal arrangement ensures that the presiding officers of the House manage their resignations within the legislative body rather than through the executive branch. The Speaker remains in office during the life of the Lok Sabha unless they cease to be a member, are removed by a resolution passed by an effective majority, or choose to resign [c3][c5]. While the President fixes the date for the Speaker's election, the resignation process is strictly internal to the Lok Sabha's presiding officers [c3][t1]. Therefore, the resignation is not addressed to the President, Prime Minister, or Chief Justice of India.

Sources

1. [1] Indian Polity, M. Laxmikanth(7th ed.) > Chapter 55: Constitutional Prescriptions > Table 55.7 Constitutional Prescriptions with Respect to Resignations > p. 461