How much can a 1-day delay in filing ITR cost taxpayers even if no tax is due?

Failing to file an ITR by July 31 can attract interest at 1% per month, calculated from the due date, along with late fees. Since interest is calculated monthly, even a one-day delay in filing ITR may attract interest on the full tax due. Filing ITR after the deadline may still attract late fees, even if no tax is due.