Kootstertille (West Frisian: Koatstertille) is a village in Achtkarspelen in the province of Friesland, the Netherlands.
Kootstertille means bridge near the village of Kooten (=little houses) which was built in 1571.
The settlement quickly outgrew Kooten, and both were officially merged in 1959 as Koostertille.
Its location along the canal which is nowadays called Prinses Margrietkanaal [nl] started to attract industry.
In the late 1930s, the canal was diverted and a little harbour was created which further stimulated development.