The overall Championship title is contested by drivers and co-drivers using cars homologated in FIA classes RC2 (R5/ Rally2), RC3, RC4, RC5 and RG-T.

The first major change to the series came in 1983, when the Rally of the Lakes attained International status and was installed as the final event in that year's championship.

[4] The addition of the Killarney-based round made up for the loss of the Galway International Rally, which did not run.

[5] The next significant change took place in 2002, when the Jim Clark Rally was added to the series,[6][7] taking the Championship to eight rounds overall.

[17][18] With COVID-19 restrictions effectively coming to an end, a full 2022 calendar was announced by Motorsport Ireland and TROA.

[29] Amidst on-going restrictions aimed at curbing the effects of the pandemic, the board of directors and executive of TROA made the unanimous decision to cancel the 2020 Championship on 28 April 2020.

[37] The ITRC is available to view on a variety of platforms, including television (TG4, BT Sport) and on demand via internet streaming services.