Subject to F3sections 261B, 261D and 263ZA and except as otherwise expressly provided, the amount of a loss accruing on a disposal of an asset shall be computed in the same way as the amount of a gain accruing on a disposal is computed.

Except as otherwise expressly provided, all the provisions of this Act which distinguish gains which are chargeable gains from those which are not, or which make part of a gain a chargeable gain, and part not, shall apply also to distinguish losses which are allowable losses from those which are not, and to make part of a loss an allowable loss, and part not; and references in this Act to an allowable loss shall be construed accordingly.

A loss accruing to a person in a year of assessment shall not be an allowable loss for the purposes of this Act unless, in relation to that year, he gives a notice to an officer of the Board quantifying the amount of that loss; and sections 42 and 43 of the Management Act shall apply in relation to such a notice as if it were a claim for relief.

A loss accruing to a person in a year of assessment during no part of which he is resident or ordinarily resident in the United Kingdom shall not be an allowable loss for the purposes of this Act unless, under section 10 F2or 10B, he would be chargeable to tax in respect of a chargeable gain if there had been a gain instead of a loss on that occasion.

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