For me, no limit rules applied. Bill was 44K+ for Indusind and paid thru smart pay smoothly without any limit/restriction.
Enabled smart pay as per this thread, received RP for ICICI (platinum & amazon pay) and Indusind CC. Received RP on very next day (business working day). If there's bank holiday or sunday, RP takes 1 or 2 days. As soon the bill generates, smart pay picks the bill and sends us text msg/email.
My account is Preferred and platinum DC is old. Whosoever have registered smart pay, they might be eligible for extra cashback (Rs 150 max per month) + vouchers per added billers. As per their T&C Smartpay should not be thru account; it should be either thru DC or CC. You can use the smart pay for cc, electricity, broadband, gas bill etc. Cashback and voucher might be provided after end of this april month and within 90 days. Other t&c usual one.
It is always good to add other utility bills so that you might be eligible for vouchers for higher values. Max bills a user can add is 10, either thru CC or DC. I noticed every month HDFC use to advertise such and this month only I see CC/DC smart pay. (earlier it was available only thru savings account for utility bills smart pay)
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