Flatlands is a local service district in Addington Parish, Restigouche County, New Brunswick, Canada. The Duncan family of Aberdeen, Scotland were the original settlers of Flatlands and Campbellton. In 1866 Flatlands was a farming and lumbering settlement with approximately 27 resident families. In 1871, it had a population of 150. In 1898 Flatlands was a station on the Intercolonial Railway and had one post office, three stores, a shingle mill, a church and a population of about 400. The population as of 2016 is 143 people.