Your company should claim the deduction in the same tax year as when the building is placed in service, but by filing an accounting method change, building owners can retroactively claim the deduction as far back as the 2006 tax year.
But unlike building owners, if an architecture, engineering, or construction entity misses the deduction on a current-year tax return, they must file an amended return to receive the deduction. A significant administrative burden can result, especially if an entity needs to retroactively claim the deduction for multiple years.
If you think your company could qualify for the Section 179D deduction, it’s important to act quickly, since only a finite amount is available for each project. The designer should receive a signed allocation letter from the government entity; it must be signed by someone within the government entity with the authority to do so.