[sofixa]

> How do credit cards provide 60 day interest free loan with only 0.3% charge to the merchants

They don't. They're rare, only do 30 days, and are often paid (you pay monthly/yearly for the pleasure).

[adrr]

30 day billing cycle with 30 days to pay. Between 30 days and 60 days before payment.

[sofixa]

Not how they work in EU countries i know of (France and Bulgaria). You have a 30 days billing period, and then around a week to pay.