Losses incurred after financial year ending 31 December 2016 can be carried forward for 17 years. Losses incurred up to financial year ending 31 December 2016 can be carried forward indefinitely.
It is clarified (vide Circular no. 31) that regular accounts are required to be maintained in order to claim the deduction of losses and any losses incurred before 31 December 2016, which are allowed to be carried forward indefinitely. Further, such losses can be deducted in priority over the losses subject to 17-year limit.
Carryback of losses is not allowed in Luxembourg.