Leinster will face Ulster in the last 16 of the Heineken Champions Cup while Munster must travel to Durban to play the Cell C Sharks.
Leinster finished top of Pool A with four bonus-point wins from four and their reward is a home tie with their interprovincial rivals, who they have already beaten twice this season.
Ulster lost their first three pool matches but scraped into the knockout stages after a 22-11 victory over Sale Sharks saw them finish eighth in Pool B.
Munster fell to another narrow loss against Toulouse, and Edinburgh's 20-14 win over Saracens means Graham Rowntree's side face two trips to South Africa in April.
Their Champions Cup tie with the Sharks will be played on the weekend of 31 March-2 April and they will return two weeks later for back-to-back BKT United Rugby Championship fixtures against the DHL Stormers and Sharks on 15 and 22 April respectively.
YOUR ROUND OF 16 MATCH UPS 📢
— Heineken Champions Cup (@ChampionsCup) January 22, 2023
Best tie? 👀#HeinekenChampionsCup pic.twitter.com/uUzz7f83LT
Elsewhere, holders La Rochelle will play Gloucester, who conceded the most points in the pool stages (140) but progressed thanks to an away win over Bordeaux-Begles on Saturday, while five-time winners Toulouse are at home to the Vodacom Bulls.
Saracens’ losing bonus point against Edinburgh means they will have home advantage against the Ospreys. Edinburgh will travel to Leicester Tigers while the DHL Stormers will host Harlequins.
In the Challenge Cup, Connacht's disappointing defeat to Newcastle Falcons means they will travel to Benetton in the last 16.
A losing bonus point against Newcastle would have been enough to secure home advantage for the Westerners, who had won their opening three games, but they crashed to a 35-21 defeat.
