Thomas William Hamilton (born December 31, 1951) is an American musician and songwriter who serves as the bassist for the hard rock band Aerosmith.

Hamilton has regularly co-written songs for Aerosmith, including two of the band's biggest successes: "Sweet Emotion" (1975) and "Janie's Got a Gun" (1989).

His father was a United States Air Force pilot in World War II and his mother was a housewife.

[3] Later, Hamilton was in several bands with future Aerosmith guitarist Joe Perry and David "Pudge" Scott.

It was at a Jam Band gig in the summer of 1970 at a venue named "The Barn" in Sunapee, New Hampshire that the group met Steven Tyler.

The three became a power trio with Hamilton on bass, Perry on guitar, and Tyler doubling as both the vocalist and drummer.

Eventually, however, Hamilton would fulfill his acting goal by joining the cast of Banned in Boston in 1996; he has been performing with them yearly since.

[7] Additionally, he has created and currently owns a line of adult-themed plush toys and merchandise called Obscenies.

[9] Hamilton left the band's April 2013 Australian tour after two shows due to a chest infection.

Hamilton now has his own G&L ASAT Bass signature model line, which is made from a unique reduced-weight Western Sugar Pine body.

"[24] For the recording of the album Honkin' On Bobo and subsequent tours, he used a butterscotch Sadowsky '51 Fender Precision Bass replica modified with a second pickup.

Additionally, Hamilton used a five-string Sadowsky to record the hits "Pink", "I Don't Wanna Miss a Thing", and "Full Circle."

Hamilton stated that he enjoys the feel of the slender Jazz Bass neck as well as its unique sounding pickups.

In an interview, Hamilton noted that he was very proud of the tone he got from his early model StingRay Bass on the Pump album.

[31] During the "Dude Looks Like A Lady" sequence of Wayne's World 2, he is seen playing a Gibson Les Paul Bass; it was occasionally used on the 1993–94 Get a Grip Tour.

Hamilton had frequently played the bass for six months prior on tour, and it was signed by all five members of Aerosmith as well as employees of Parker Guitars.

In 2023, Hamilton sent a sizeable portion of his instrument and equipment collection to Donn's Drum Vault in Bellevue, MA to be offered for public sale.

[41] Apart from this, Hamilton plays with suspended chords (e.g. "Sweet Emotion"), and also uses open strings to form a low drone sound; he frequently jumps to higher registers so that his notes can ring out.