Semiquincentennial Congressional Time Capsule Act

The law requires the Architect of the Capitol to build a "Semiquincentennial Congressional Time Capsule" containing a joint letter from the top Republican and Democratic leaders of the House and Senate, plus any other items those offices jointly choose, so long as the materials pose a low risk of degrading. The capsule has maximum size limits, and the Architect must bury it, sealed, in the Capitol Visitor Center by July 4, 2026, with approval from the House Administration and Senate Rules and Administration committees, timed so attendees can also attend a related time capsule burial in Philadelphia. The capsule is to remain sealed until July 4, 2276, when the Speaker of the House and Senate Majority Leader are to present it to the 244th Congress, which will decide how to preserve or use its contents. The law creates no ongoing program, funding, or regulatory authority beyond this one-time project.

The Architect of the Capitol, who must build, seal, and bury the capsule; the offices of the House Speaker and Minority Leader and Senate Majority and Minority Leaders, who choose its contents; and the House Administration and Senate Rules and Administration committees, who must approve the burial location and plaque.

The law creates a symbolic historical marker tied to the nation's 250th anniversary rather than any operational or regulatory change. Its main practical effect is on Capitol facilities planning and a ceremonial event in 2026, with the substantive unsealing not occurring for 250 years.