Catherine Ardagh (born 20 September 1982) is an Irish Fianna Fáil politician who has served as a Teachta Dála (TD) for Dublin South-Central since November 2024.

[6] In December 2019, an RTÉ investigation revealed that Ardagh, Fianna Fáil's leader in the Seanad, did not participate in 68 out of 120 voting days where she was recorded as present in Leinster House between June 2016 and July 2019.

Ardagh received her full Travel and Accommodation Allowance (TAA), totalling approximately €13,500 from 2016 to 2018, and stated that she contributed to Seanad debates as part of her leadership responsibilities.

In February 2021, Catherine Ardagh publicly shared her physical challenges with undergoing five rounds of in vitro fertilization (IVF), which led to the birth of her twin sons.

In the Seanad, Ardagh called for greater State support for couples facing fertility challenges, advocating for free IVF in public hospitals.

Ardagh criticized the lack of engagement from the school and highlighted the stress faced by parents of children with disabilities, describing it as deeply isolating.

In 2020 Ardagh advocated for a State-funded crèche system to support working mothers, describing it as a sensible economic and social investment, though it was not included in Fianna Fáil's manifesto.