Bolton was born Michael Bolotin in New Haven, Connecticut, the son of Helen (née Gubin; 1919–2015) and George Bolotin (1912–1981). He has a brother, Orrin, and a sister, Sandra, both older. His family was Jewish. His maternal grandmother was born in England to Russian Jewish parents, and his other three grandparents were Russian Jewish immigrants.

Since 1975, Bolton has released at least 17 studio albums and 35 singles. Nine of his singles have peaked at No. 1 on either the Billboard Hot 100 or the Hot Adult Contemporary Tracks charts in the US. He has also released numerous compilation albums and three Christmas albums.

Bolton would achieve his greatest success in the late 1980s and early 1990s as a singer on the adult contemporary/easy listening charts. One of his first major hits was his 1987 interpretation of the Otis Redding classic "(Sittin' On) the Dock of the Bay". Redding's widow, Zelma Redding, said she was so moved by Bolton's performance "that it brought tears to my eyes. It reminded me so much of my husband that I know if he heard it, he would feel the same." Always interested in soul and Motown classics, Bolton's success with that song encouraged him to tackle the standard "Georgia on My Mind", with which he had another hit. In 1991, Bolton released the album Time, Love & Tenderness which featured his Grammy Award-winning cover version of "When a Man Loves a Woman".

After Anglicizing his family name to Bolton, he gained his first major hit as a Songwriter, co-writing "How Am I Supposed to Live Without You" for Laura Branigan, previously best known for singing the pop hit "Gloria". Narrowly missing the Top 10 on the US pop chart, Branigan took the song to number one on the Adult Contemporary chart for three weeks in 1983. The two sought to work with each other again, and their next collaboration was when Bolton co-wrote "I Found Someone" for Branigan in 1985. Her version was only a minor hit, but two years later, Cher resurrected the song, and with it her own singing career. Bolton co-wrote several other songs for both Singers.

Bolton was introduced to Actress Nicollette Sheridan in 1992 by adult contemporary/jazz Saxophonist Kenny G. Bolton and Sheridan dated until 1995, stopped dating, then reunited in 2005 and became engaged in March 2006; however, it was confirmed in August 2008 that they had broken off their engagement.

On July 25, 1993, Michael Bolton played against Michael Jordan in a televised charity softball game at the Chicago White Sox stadium, Comiskey Park. Michael Bolton's team, The Bolton Bombers, won the game 7-1 against Michael Jordan's team, Jordan's Air Force. The Bolton's Bombers were composed of Michael Bolton and his band while the Jordan's Air Force was composed of celebrities including Magic Johnson, Chris Chelios, Ahmad Rashād, Mark Harmon, MC Hammer, Tom Selleck, Stacey King, and Bo Jackson as coach.

A Los Angeles jury ruled in favor of the Isley Brothers on April 25, 1994. The jury determined there were five instances in which Bolton's song plagiarized the Isleys' tune. Bolton, co-writer Andrew Goldmark and Sony Publishing were ordered to turn over more than $5 million in profits from the sales of Bolton's version of the song to the Isley Brothers. It was the largest award in history for plagiarism in the music industry.

Bolton's last Top 40 single in the US in his own right was the 1997 hit "Go the Distance" (featured in the Disney animated motion picture Hercules), which peaked at No. 1 on the US adult contemporary chart. He hired Conductor Larry Baird (orchestral musical director/conductor/arranger for The Moody Blues, Three Dog Night, Al Jarreau, etc.) for his 2001 tour.

Bolton, Goldmark and Sony appealed the verdict, and the court fight continued for nearly seven more years. The case came to a close on January 22, 2001, when the Supreme Court of the United States refused to hear the appeal of a May 2000 decision by the Ninth Circuit Court Of Appeals in San Francisco.

In March 2003, Bolton joined with Lifetime Television, Verizon Wireless, and many others to lobby on behalf of the National Coalition Against Domestic Violence, urging legislation to provide more assistance for victims of domestic violence, such as affordable housing options.

In August 2006, Bolton was one of Lucy Lawless's duet partners on the Fox network's program Celebrity Duets, which Simon Cowell's Syco Productions Company produced for the network.

Bolton performed a duet entitled "Il Mio Amico" with the Italian singer Anna Tatangelo at the Sanremo Music Festival 2008. The song was originally sung by Tatangelo alone, but the duet version contained English lyrics as well.

Bolton's album Only a Woman Like You was released in 2001. The title song was co-written by Shania Twain. Bolton released his album One World One Love in the UK on September 21, 2009. The first single, "Just One Love", was released one week earlier.

Bolton was married to Maureen McGuire, but they divorced. They are the parents of three adult daughters: Isa, Holly, and Taryn. Taryn gave birth to a daughter in October 2010.

In 2011, Bolton was featured as a guest vocalist in The Lonely Island's song "Jack Sparrow" on their Turtleneck & Chain album. His performance with the comedic hip-hop trio focused on his (intentionally) off-topic chorus and miscommunication with the group, and the video featured him dressed in costumes as Jack Sparrow from Pirates of the Caribbean, Forrest Gump, Erin Brockovich, and Tony Montana from Scarface.

In January 2013, Bolton published an autobiography, The Soul of It All: My Music, My Life.

In 2015, Bolton starred in a Pizza Hut commercial as himself singing Jingle Bells while the family opens up their pizza order.

In 2018, Bolton announced his intention to do a tour performance in Birmingham, the UK in November 2018, after two years since last time he visited the UK.