Can I carry forward a business loss if I file my income tax return late?

Generally no. A business loss can be carried forward to later years only if the return for the loss year was filed on or before the due date. A belated return still lets you file, but the business loss is not allowed to be carried forward, with the exception of loss from house property.

Where the return is filed in time, a non-speculative business loss can be set off against business profits of the next 8 assessment years. Since your own facts matter here, confirm the position with your CA or tax advisor.