Symmons Plains Estate is a historic farm and mansion in the locality of the same name, near Perth, Tasmania. A 856ha property,[1] the estate dates back to 1820s, with the main Georgian house built in 1839.[2] It is listed on the Tasmanian Heritage Register.[3] In 1978, the homestead and its garden and outbuildings were registered on the now-defunct Register of the National Estate.[4]