Taxes Consolidation Act 1997 section 678

Allowance for machinery and plant

Section 678 provides for a special 20% investment allowance in respect of new machinery or plant used in the trade of working a qualifying mine, in addition to normal capital allowances.

• New machinery or plant (excluding road vehicles) provided for use in working a qualifying mine on or after 6 April 1974 is deemed to be qualifying machinery or plant for capital allowance purposes.
• A supplementary investment allowance of 20% of the capital expenditure applies to new mining machinery or plant, but only for expenditure incurred on or after 6 April 1974 and before 1 January 2011.
• The 20% investment allowance is disregarded when applying the rule that total capital allowances cannot exceed the cost of the asset, and the allowance is withdrawn if the asset is sold or ceases to be used within two years.
• A claim for the investment allowance must be included with the income tax or corporation tax return, accompanied by a signed certificate confirming the expenditure was on qualifying machinery or plant.