The President of the U.S. Senate is the Vice President of the United States. As of now, the Vice President serves as the President of the Senate, presiding over Senate sessions and having the authority to cast tie-breaking votes

. The President pro tempore of the U.S. Senate, who presides in the absence of the Vice President, is currently Chuck Grassley, serving since January 3, 2025. This position is traditionally held by the most senior member of the majority party and is third in the presidential line of succession after the Vice President and the Speaker of the House

. In summary:

• President of the Senate: The Vice President of the United States (current officeholder not specified in the search results but traditionally the sitting Vice President).
• President pro tempore of the Senate: Chuck Grassley (since January 3, 2025)