Colorado property taxes are assessed by:

The state does not assess property taxes in Colorado. While the state sets some overall policies and assessment rate limitations, the actual assessment and valuation process is handled at the county level, not by the state government.

The federal government does not assess property taxes in Colorado or any state. Property taxation is a state and local function, with no federal involvement in individual property assessment or valuation.

While municipal governments do collect property taxes once assessed, they do not perform the assessment function. Assessment is solely the responsibility of county assessors in Colorado's structure.