The authority has said it plans to raise fares every two years, but the climbing cost has frustrated riders who complain of worsening subway delays, overcrowding and slow buses. Under the last fare and toll increase, in March 2015, the base fare for subways and buses rose by a quarter to $2.75.

The authority’s chairman, Thomas F. Prendergast, said the “modest” increases, set to take effect on March 19, were needed to cover rising costs.

“The M.T.A. continues to keep its promise to make sure that fare and toll increases, while necessary to keep our system running, remain as low as possible and that they are done in as equitable a way as possible,” Mr. Prendergast said.

The regularly scheduled increases are part of a financial rescue plan approved by the New York State Legislature in 2009. Officials at the authority argue that its policy is better than those of other transit systems, like New Jersey Transit, whose fare increases, including a 9 percent rise last year, are less predictable. They said fares and tolls paid for about half of the authority’s annual operating budget.

With another fare increase on the horizon, some transit advocates and elected leaders have called on Mayor Bill de Blasio, a Democrat, to pay for a program to offer half-price MetroCards to New Yorkers living in poverty. The Seattle area introduced discounted fares for low-income riders last year and has already signed up tens of thousands of people.