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The Beach Boys have been known to perform and/or record a number of songs, instrumentals, and early versions of compositions which have never been officially released on a single, album, or compilation. Only those whose existence can be reliably confirmed are listed here. Some bootleg recordings of the below listed songs are in circulation while other recordings have been lost and unheard of since their creation.

This list is ordered by recording date. It does not include the innumerably non-substantial rehearsal tapes, instrumental tracking, and session chatter recorded by the group.

Adapted from Andrew Doe, except where otherwise noted.

Brian Wilson, Roger Christian, and Gary Usher song recorded on April 16, 1962.

Brian Wilson and Gary Usher song recorded on April 16, 1962. Also known as "Human".

Brian Wilson and Gary Usher song recorded on April 16, 1962.

Brian Wilson and Gary Usher song recorded on April 16, 1962. Also known as "Number One".

Brain Wilson, Bob Norberg, and Pomeroy song recorded in 1962.

Brian Wilson song recorded on January 18, 1963. No vocal was recorded.

Al Jardine instrumental recorded in February 1963.

Brian Wilson and Jan Berry song recorded in spring 1963.

Brian Wilson and Roger Christian song recorded in the summer of 1963.

Brian Wilson, Gary Usher, and Roger Christian song recorded in mid 1963.

Brian Wilson instrumental recorded on August 5, 1963.

Brian Wilson song produced for singer Dave Nowlen on August 5, 1963.

Brian Wilson song recorded on August 5, 1963.

Brian Wilson song recorded in August 1963.

Brian Wilson song recorded in January 1964. No vocals.

Brian Wilson song recorded in January 1964.

Cover of Irving Berlin song recorded on October 15, 1965.

Cover of Washington/Young song recorded on October 15, 1965. Instrumental.

Brian Wilson song recorded in spring 1967 with lead vocals by Jasper Dailey.

Brian Wilson song recorded in spring 1967 with lead vocal by Jasper Dailey.

Traditional song recorded on April 11, 1967. May feature Brian and Paul McCartney on lead vocals.

Uncertain if Brian Wilson song; recorded on June 11, 1967.

Uncertain if Brian Wilson song; recorded June 11–21, 1967.

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