|Length:||19.5 km (12.1 miles)|
|Meets:||R320, N17, N60|
The R323 runs from the R320 in Kiltimagh to the N60 at Hazelhill, close to Ballyhaunis. It formerly ran into the centre of Ballyhaunis but a relief road now takes it to a point on the N60 a kilometre southwest of the town centre. There is a grade-separated junction with the N17 at Knock.