Your net investment income includes your interest, dividend, annuity, royalty, and rental income, unless those items were derived in the ordinary of property, other than property held in an active trade or business, is also subject to the tax. 30 Sep 2014 1411 was intended to prevent individuals in real property trades or businesses that own ancillary rental real estate activities from qualifying for the 17 Dec 2019 The net investment income tax (NIIT) is a surtax on high amounts of investment interest expenses and any costs involved with rental and