The company says the The 155, which will be launched next month, will run from IKEA -- stopping in the city centre and Dun Laoghaire -- before terminating in Bray.
The new service is scheduled to operate every twenty minutes.
Meanwhile, nine more bus routes have switched from Dublin Bus to private operator Go-Ahead Ireland
Route 17 serves Blackrock to Rialto, and the 114 runs from Blackrock to Ticknock, along with the 104, 161, 220, 236, 238, 239, and 270
It's the latest phase of changes being introduced on about 50 bus routes in Dublin, operated under the Transport for Ireland brand, by both Dublin Bus and Go-Ahead Ireland.