Best add-on credit card for spouse in India

Forex markup comparison: Amex = 3.5%, HDFC Infinia/Diners Black = 2.0%, Axis Atlas = 3.5% but with milestone fee waivers, ICICI Emeralde = 3.5%, Standard Chartered = 3.5%. If you travel more than twice a year, the math favours Infinia or Diners Black.

I've held this card for 3 years. Quick reality check: the welcome benefit is good, the first-year fee waiver is easy, but from year 2 onwards you really have to work for the milestone benefits. Don't keep it if your monthly spend drops below the milestone threshold.