Ulster will open their first European Champions Cup campaign with a trip to Leicester on Saturday 18 October.
The Irish province ended Leicester's unbeaten home run of 25 Heineken Cup matches last January but it will still represent a tough opener for Ulster.
Ulster will then host holders Toulon on 25 October before back to back to games against the Scarlets in December.
Precise dates and times have only been arranged for the opening two rounds in the new European competition.
Ulster will face the Scarlets on the weekend of 4-6 December before travelling to Wales the following weekend.
The two remaining rounds in the pools will take place on 16-18 January and the following weekend with Ulster facing Toulon away before their final group fixture at home to Leicester.
Pro12 holders and three-times Heineken Cup winners Leinster will open their Pool 2 campaign against Wasps at the RDS on 19 October with Munster facing Sale away in Pool 1 the previous evening.
Munster's second fixture will see up them hosting last season's beaten Heineken Cup finalists Saracens on 24 October with Leinster away to Castres two days later.
Leinster will take on Harlequins in back to back games in December with Munster facing home and away tussles against French giants Clermont Auvergne.
Munster will be away to Saracens on the weekend of 16-18 January before hosting Sale a week later while Leinster's last two Pool 2 fixtures will see them at home to Castres and away to Wasps.