The average price for gas across Indiana and in Putnam County is $1.70 per gallon today, according to GasBuddy. That’s down five cents from where it was Monday. The cheapest gas in the state is in Merrillville where it’s $1.14. Gas prices continue to go down because of the coronavirus. GasBuddy advises you to wait as long possible to fill up because prices will continue to go down.