In early 2000, Banfield was hired by national cable network MSNBC after having won an Emmy for her reporting at Dallas broadcast station KDFW-TV.

[7] On September 11, 2001, Banfield was reporting from the streets of Manhattan amid a cloud of debris from the collapsing World Trade Center.

[8] After the initial reporting of the attack had ended, Banfield received a promotion, as MSNBC sent her around the world as the producer of a new program, A Region in Conflict.

[9] Banfield lost two friends in the World Trade Center attacks and sought help for post-traumatic stress disorder.

[12] In April 2003, in a Landon Lecture Series speech at Kansas State University, Banfield raised concerns regarding media coverage of the conflict in Iraq.

[13] The New York Times reported that her speech angered MSNBC-controlling NBC management, who rebuked her and lowered her profile.

[15] Banfield joined CNN in January 2012 as co-anchor with Zoraida Sambolin, of the network's morning show, Early Start.

[16] On August 13, 2012, Banfield moved to the 11 a.m. edition of CNN Newsroom in New York each weekday, replacing Kyra Phillips as anchor.

[18] In 2014, Banfield was featured in a small role portraying herself in the Netflix series House of Cards, where she interviewed Claire Underwood.

On October 16, 2018, it was announced by HLN that Banfield was to be laid off, along with Michaela Pereira and Carol Costello, as part of the network's decision to scale back their live news programming.

[20] She resumed hosting programs on CourtTV, including the true crime documentary series Judgment with Ashleigh Banfield in 2020.

[23] She was known for her "trademark rectangular eyeglasses, the object of countless remarks, pro and con, after her arrival on the national media scene.

[26] On December 29, 2017, Banfield's 50th birthday, she married sales executive Chris Haynor, her partner of three years, at the Hermitage Club ski lodge in Wilmington, Vermont.