Clontarf is an affluent coastal suburb on the Northside of Dublin in the city's Dublin 3 postal district. Historically, there were two centres of population, one on the coast towards the city, and the fishing village of Clontarf Sheds, further north on the coast at what is now Vernon Avenue. Clontarf has a range of retail businesses in several locations, mainly centred on Vernon Avenue. It adjoins Fairview, Marino, Killester and Raheny. Clontarf is in the jurisdiction of Dublin City Council.

The Northside in an informal but commonly used term to describe the part of the city of Dublin that lies to the north of the River Liffey, and extending into part of North County Dublin. The part outside the city is within the county of Fingal, a local government area established in 1994. While it is sometimes regarded as less wealthy than the city's Southside, the Northside was originally the home of the city's upper classes and the more privileged of the two. Today, some of the wealthiest areas in Ireland, such as Malahide, Howth, Clontarf, and Castleknock, lie north of the river.