Leinster will host Benetton in their opening Pool One game of the 2019/20 Heineken Champions Cup on Saturday November 16th.
Connacht begin their European campaign with Montpellier visiting the Sportsgrounds on Sunday November 17th.
Leinster will travel to Lyon on November 23rd and Northampton Saints on December seventh. The return fixture takes place a week later in the Aviva Stadium on December 14th.
Round five see’s Leinster host Lyon in the RDS on January 12th and round out their campaign away to Benetton on January 18th.
Connacht travel to Toulouse in round two on November 23 and again to Gloucester on December eighth with the return meeting in the sportsgrounds on December 14.
In round five Connacht host Toulouse at January 11th and round out their group campaign away to Montpellier on January 19th.
Ulster open their campaign away to Bath on November 16 and Munster travel to Ospreys on the same day.