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King County Department of Assessments

Setting values, serving the community, and promoting fairness and equity.

Department of Assessments

201 South Jackson Street, Room 708
Seattle, WA 98104

Office Hours:
Mon - Fri
8:30 a.m. to 4:30 p.m.

TEL: 206-296-7300
FAX: 206-296-5107
TTY: 206-296-7888

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Glossary of terms for commercial parcels

Anything done to raw land with the intention of increasing its value.  A structure erected on the property constitutes one very common type of improvement, although other actions, such as those taken to improve drainage, are also improvements.

Buildings, other structures, and attachments or annexations to land that are intended to remain so attached or annexed, such as sidewalks, trees, drives, tunnels, drains and sewers.

The income approach defines value as the present worth of future benefits arising from the ownership of a property. This definition reflects the principle of anticipation.  Income-producing property typically is purchased for the right to receive the future income stream of the property.  The assessor analyzes this income stream in terms of quantity, quality, and duration and then converts it by means of an appropriate capitalization rate into an indication of market value. The basic formula is:  Value equals income divided by rate.