Qatar Airways and United have round-trip flights from Houston (IAH) to Mumbai (BOM) for $657-$681 with a connection. Flights September, October, and March. Departures on Monday, Tuesday, and Wednesday. 7-day minimum stay required.
Note: Mumbai has been at this price level since February 2019.
Note: Some small OTAs on SkyScanner have this for $625. If you plan on booking there, beware of any site that charges a fee to cancel a ticket within the 24-hour “free” period. Use unknown booking sites at your own risk.