The $65 million in funding toward the MTA that Gov. Andrew Cuomo has proposed to cut from his state budget could be used for a variety of improvements in service, according to a new report.

All told, the transit agency is receiving a $30 million increase in state funding through the proposed 2018 fiscal year budget — a bump from $4.456 billion to $4.486 billion — thanks to additional revenue coming in from dedicated taxes, like the payroll mobility tax. But Cuomo is falling back on that added revenue to justify a $65 million reduction in promised MTA dollars from the state’s general fund.

“This money was promised to transit riders, and if Gov. Cuomo wants to be a champion for transit, he should back away from his threat to cut MTA funding,” said John Raskin, executive director of the Riders Alliance, in a statement. “Delays are up, crowding is worse and people notice it every day in their commutes. This should be a time when Gov. Cuomo adds funding to mass transit, not a time when he takes away funds that were supposed to be guaranteed.”

A joint budget analysis released Sunday by Riders Alliance and the Regional Plan Association highlights that another $65 million for the MTA, which boasts a $27 billion five-year capital plan, could go a long way in reducing crowding and delays.

With that money, the state-run MTA could purchase 21 additional subway cars featuring open gangways, or repair more than 500 aging subway cars, according to the analysis. The agency could bring Americans with Disabilities Act accessibility to one, possibly two, subway stations (only about a quarter of all subway stations are ADA-accessible).

It would require $28 million annually for the MTA to increase bus service to the extent that the agency could create a “new citywide standard” in which all buses would arrive at least every 10 minutes at rush hour, 15 minutes at other times and 20 minutes on weekends, according to the analysis.

The $65 million could bring five new bus routes online, or more than 3,000 countdown clocks to bus stops, the analysis showed.

After the payroll mobility tax was restructured in 2011, Cuomo pledged to make the agency whole, and has done so by committing just about $300 million from the state’s general fund each year. The upcoming budget, due April 1, plans to scale back that allocation from $309 million last year to $244 million.

“If these cuts are adopted, we’ll see more delays, more crowding and more traffic on our streets as commuters throw up their hands and opt to avoid mass transit altogether,” said Tom Wright, president of the Regional Plan Association, in a statement.

The report combats the Cuomo administration as well as MTA executives appointed by the governor, who have stressed the state’s net increase in MTA funding in the budget.

“Math can be tricky but calling an increase a cut is absurd even by the advocates’ standards,” said Jon Weinstien, a spokesman for the governor, in a statement issued Sunday.

Correction: This story was updated to address an inaccuracy in the joint report from the Riders Alliance and Regional Plan Association. An increase of $65 million in MTA funding could support renovations to add ADA accessibility to between one and two subway stations. The original report stated that the money could support ADA renovations for eight stations.