# Companies Act 1985, Paragraph 18

Extent: E+W+S

In the case of any fixed asset which has a limited useful economic life, the amount of—
(a) its purchase price or production cost; or
(b) where it is estimated that any such asset will have a residual value at the end of the period of its useful economic life, its purchase price or production cost less that estimated residual value;
shall be reduced by provisions for depreciation calculated to write off that amount systematically over the period of the asset’s useful economic life.

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Source: https://www.legislation.gov.uk/ukpga/1985/6/schedule/4/paragraph/18 (the official version)
Page: https://openlegislation.uk/companies-act-1985/schedule-4/paragraph-18
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.