Advance tax payment on sunday

You are not liable to pay any interest.
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In case of e-payment of taxes, payments made up to 8.00 pm will be treated as received on the same day and those received thereafter be treated as received on next working day.
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- Notification No. RBI/2007-08/275, dated 03.04.2008
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If the last day for payment of any installments of advance tax is a day on which the receiving bank is closed, the assessee can make the payment on the next immediately following working day, and in such cases, the mandatory interest leviable under sections 234B and 234C of the Income-tax Act, 1961 would not be charged.
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- Circular No. 676, dated 14.01.1994