BART is offering half-off fares for people using Clipper during the entire month of September, according to the transit agency.

The reduced fare, available for those using the Clipper card or smartphone app, is an effort by the transit agency to encourage riders to come back to the system, which is still seeing only about 25 percent of its pre-COVID weekly ridership numbers and 40 percent of its weekend ridership.

Clipper is free when set up using the new Clipper smartphone app or when a card is ordered online and set up for automatic reloading of funds. The card costs $3 if purchased at a station vending machine.

Other transit agencies in the Bay Area are also offering discounts and promotions during September. More information about the programs can be found online.