THE MBTA SHOULD EXPERIMENT with income-based fares and cut charges for reverse-commuting and off-peak travel, the think tank MassINC argues in a new policy brief.

The brief doesn’t advocate for specific commuter rail fares, but notes that the cost of travel between most Gateway Cities and Boston is way too high. The fare cost as a percentage of a community’s median household income ranges from 6 percent in Lynn and Salem to 13 percent in Worcester and Lawrence. In Greater Boston’s wealthy western suburbs, the percentage is in the 2 to 4 percent range.

There is some evidence that MBTA riders, particularly low-income passengers, tend to board public transit more if the price is affordable. The brief draws a direct link between fare equity and transit-oriented development in Gateway Cities, but urges experimentation on how much to cut fares, in part because of fears that lower fares for Gateway City residents could lure them to travel to Boston for jobs and leave their hometowns without enough workers.

The MassINC policy brief also urges lowering fares for reverse commuters, those leaving Boston for jobs outside the city, and at off-peak times.

MassINC is the nonprofit parent of CommonWealth magazine.