In accounting, impairment is a permanent reduction in the value of a company asset. It may be a fixed asset or an intangible asset.

 When testing an asset for impairment, the total profit, cash flow, or other benefits that can be generated by the asset is periodically compared with its current book value. If the book value of the asset exceeds the future cash flow or other benefits of the asset, the difference between the two is written off, and the value of the asset declines on the company's balance sheet.