If u got a normal atm card, u can juz use it to activate ur debit card at the atm machine. then u dun need to send back the acknowledgement slip. after activating the debit card at the atm machine, u can use it immediately..Originally posted by cloudymind:for those with posb mastercard debit card, if you intent to activate the card using atm do you still need to return the acknowledgement of debit card portion that comes with your debit card in the mailer?