Born in County Clare, Coughlan first began playing rugby aged 11 with Ennis, with whom he won an under-16 title in 2018 and a shared under-18 cup in 2020.
In 2020, Coughlan joined famous Clare club Shannon to play in the amateur All-Ireland League.
During the 2020–21 season, he trained with Munster's senior squad on several occasions, providing cover at scrum-half during periods of injury and international absence,[3] and travelling with the matchday squad for league and European fixtures, whilst also representing the province at 'A' level.
[1] Following the disruption caused by the province's recent tour to South Africa, Coughlan made his senior competitive debut for Munster in their opening 2021–22 Champions Cup fixture away to English club Wasps on 12 December 2021, coming on as a replacement for Conor Murray in the province's 35–14 win,[4] alongside fellow Ennis RFC men Conor Moloney and Tony Butler.
[2] He was selected in the Ireland under-20s squad for the 2022 Six Nations Under 20s Championship when it was announced in January 2022,[6] and made his competitive debut for the under-20s in their tournament-opening 53–5 win against Wales on 4 February, coming on for starting scrum-half Matthew Devine in the 52nd minute.