A corporate tax entity can choose to "carry back" a tax loss it had for 2019 - 20, 2020 - 21, 2021 - 22 or 2022 - 23 against the income tax liability it had for 2018 - 19, 2019 - 20, 2020 - 21 or 2021 - 22.

The entity gets a refundable tax offset for 2020 - 21, 2021 - 22 or 2022 - 23 that is a proxy for the tax the entity would save if it deducted the loss in the income year to which the loss is "carried back".

The refundable tax offset:

  (a)   is capped at the entity's franking account balance; and

  (b)   is only available for losses for years for which the entity's turnover was less than $5 billion.