Fly nonstop from Washington D.C. to Indianapolis for $89 round-trip on United. Summer travel is available! If you reside in Indy, you can also get this same price on flights from Indianapolis to Washington D.C.
I was able to find seats over the 4th of July holiday departing Washington D.C. IAD on Tuesday, July 3, returning from Indianapolis IND on Tuesday, July 10.
Other dates are also available for travel on Tuesdays and Wednesdays, from April through August. A few Saturdays are available in April/May.
This is a basic economy fare, which means it only includes a small personal item (small backpack, large purse, etc.). Checked bag fees start at $25 each way. On this itinerary, you may upgrade to standard economy, which includes a normal carry-on bag plus personal item, for $48 more, bringing the total to $137 round-trip.
Need a room in Indianapolis? Here's what's available for the above dates on Hotelwatchdog.