Base rate entity company tax rate From the 2017–18 income year, companies that are base rate entities must apply the lower 27.5% company tax rate. A base rate entity is a company that both: has an aggregated turnover less than the aggregated turnover threshold – which is $25 million for the 2017–18 income year 80% or less of their assessable income is base rate entity passive income – this replaces the requirement to be carrying on a business. Base rate entity passive income