[3] Archer was part of the team that defeated newly crowned Heineken Cup champions, and arch-rivals, Leinster 19–9 in the 2011 Magners League Grand Final on 28 May 2011.

[9] Archer made his 150th United Rugby Championship appearance in Munster's 37–28 win against Italian side Benetton in round 20 of the 2018–19 season on 12 April 2019.

[10] He won his 200th cap for Munster in their 2019–20 Pro14 round 7 fixture against Edinburgh on 29 November 2019, becoming the eleventh player to achieve the accolade for the province.

[16] Archer earned his 250th cap for Munster in their 2022–23 United Rugby Championship round three fixture against Italian side Zebre Parma on 1 October 2022, coming in as a replacement for Keynan Knox.

He received his first senior call-up when he was selected in the Ireland Wolfhounds squad for their game against England Saxons in January 2012.

[21] Archer was selected on the bench for Ireland's 2013 Six Nations Championship game against France on 9 March 2013, his first senior call-up,[22] though he did not come on during the 13–13 draw.