Northern Ireland at home in Nations League opener
Northern Ireland will host Bosnia and Herzegovina in their Uefa Nations League opener on Saturday 8 September.
Michael O'Neill's men will then have two away fixtures in League B Group 3 against Austria on Friday 12 October and the Bosnians on Monday 15 October.
Their final match is at home to Austria on Sunday 18 November.
The Republic of Ireland's first match is away to Wales on Thursday 6 September, followed by home to Denmark on Saturday 13 October.
Next up for Martin O'Neill's side will be an encounter with Wales in Dublin on Tuesday 16 October, then finally away to Denmark on Monday 19 November.
The draw for the inaugural Nations League took place in Lausanne, Switzerland, on Wednesday, with both Northern Ireland and the Republic among the Group B nations.
Northern Ireland have not met Austria since the 2006 World Cup qualifiers, and have never faced Bosnia & Herzegovina.
The venues for the away games will be confirmed in due course.
"I think it's a good draw, an interesting draw, and the whole concept of the competition is interesting and really exciting," said NI manager Michael O'Neill.
"In my tenure we have not played against Austria or Bosnia so it's a new challenge for me as a coach as well.
"The main thing is that the competition has two parts to it - obviously it offers a possible route to Euro 2020 but it also has the promotion and relegation element to it and if you can progress into League A the quality of games you can get for the tournament next time it comes round would be fantastic."
During the international windows this autumn Michael O'Neill's side will also be playing two friendlies, to be staged on Thursday 11 September and Thursday 15 November, with opposition and venues still to be agreed.
Denmark thrashed the Republic 5-1 on aggregate in the World Cup play-offs to reach Russia 2018, with the Irish having beaten Wales 1-0 in their final group game to finish runners-up and reach the knockout stage.
"Our draw is deja vu really as Wales and Denmark were the last two nations that we played. There was initial scepticism about the competition but I am a fan," said Republic boss Martin O'Neill.