My partner (Japanese, Japan resident) would like to start a business that necessitates trips to rural Japan. They have no income from the business yet. At what point is it possible to consider the travel as a business expense for tax deduction purposes? Can it be expensed “retroactively” after the income is made? For example, trip is made in January 2026, finally income is made in May 2026 — can the January trip be expensed for calendar 2026?
by ChillyGut