Allowable Business Investment Loss (ABIL)

An allowable business investment loss (ABIL):

is 50% of a business investment loss
is treated differently from allowable capital losses in that it can be used to reduce all sources of income
can be carried back or carried forward as a non-capital loss. See the glossary item non-capital loss for carry-back and carry-forward periods.
if unused after 10 years can then be treated as a net capital loss and carried forward indefinitely to be deducted against taxable capital gains

For further information see Business investment loss on the Small Business page.