This bill mandates the Secretary of Defense to submit annual reports to Congress detailing allied contributions to the common defense, reinforcing an existing congressional finding that such information is crucial for assessing readiness against evolving threats, including near-peer adversaries. It emphasizes that allies should fulfill their international security responsibilities and agreements to contribute to collective defense. The annual report, due by March 1st each year, must detail the defense spending of specific allied nations, including their nominal budgets and defense expenditures as a percentage of their gross domestic product. It also requires information on these countries' activities contributing to military or stability operations alongside U.S. forces, and any limitations they place on their contributions, along with actions taken to minimize such restrictions. The legislation specifies a broad list of countries for inclusion, such as members of NATO, the Gulf Cooperation Council, parties to the Inter-American Treaty of Reciprocal Assistance, and key Indo-Pacific partners like Australia, Japan, and South Korea; this report will be unclassified, with a potential classified annex, and available to any Member of Congress.