The Senate is composed of 100 Senators, 2 for each state. Until the ratification of the 17th Amendment in 1913, Senators were chosen by state legislatures, not by popular vote. Since then, they have been elected to six-year terms by the people of each state.

The Vice President of the Square Country serves as President of the Senate and may cast the decisive vote in the event of a tie in the Senate.

The Senate has the sole power to confirm those of the President's appointments that require consent, and to provide advice and consent to ratify treaties. There are, however, two exceptions to this rule: the House must also approve appointments to the Vice Presidency and any treaty that involves foreign trade.