McNeil began her acting career on the soap opera As the World Turns in 1981. In 1982, she appeared in the low-budget comedy Beach House. The following year, she starred in the slasher film The House on Sorority Row. 1985 saw Kate McNeil appearing in the miniseries Kane & Abel and in 1986 she was featured in another miniseries, North and South Book II. She co-starred in Director George A. Romero's horror film Monkey Shines in 1988. In the 1990s, Kate McNeil appeared as Janet Gilchrist in the final three Waltons TV movies.
In the early 1990s, McNeil was a cast member of two television shows, WIOU and Bodies of Evidence. Kate McNeil has also made numerous television guest appearances. She has appeared on Amazing Stories, Simon & Simon, Designing Women, Midnight Caller, Quantum Leap, The X-Files, Murder, She Wrote, Babylon 5, Diagnosis Murder, Veronica Mars, Bones, The Mentalist, and Mad Men.
