Mamdani is promising a cheaper New York. But can he afford to pay for it?

The Democratic candidate in the New York City mayoral race will need billions of dollars to fund many of these campaign pledges, but it is far from certain he will be able to deliver.

The city’s mayor doesn’t have the authority to increase the taxes that Mamdani has proposed. If elected, Mamdani would need to persuade state lawmakers, including those in rural and suburban districts, to pass his tax plan.

Critics of Mamdani, including rival former Gov. Andrew Cuomo, say his plans are misguided and doomed to fail, in part because Democratic Gov. Kathy Hochul opposes the tax increases the 34-year-old state Assemblyman has touted.

Mamdani, a democratic socialist, has made his affordability agenda the core of his campaign, and it has propelled him to a double-digit lead in the polls ahead of the Nov. 4 general election.

What is Mamdani’s tax plan?

Mamdani has said he wants to generate $9 billion in new tax revenue by raising taxes on New York City’s wealthiest residents and businesses. He is calling for a 2% tax on incomes over $1 million, which would produce $4 billion in tax revenue. He wants to increase the state’s corporate tax rate to 11.5% to match New Jersey’s, generating about $5 billion annually.

He has said he would be aggressive in auditing city taxpayers and collecting fines, and would overhaul city contracts. His campaign projects potential savings of about $1 billion annually.

Raising taxes on the wealthy and corporations needs approval from the Democratic-controlled state Legislature and Hochul, who is up for re-election in 2026. Hochul, who has endorsed Mamdani, has said that she fears raising taxes will force some wealthy residents to leave New York.

Mamdani has support of key lawmakers. Senate Majority Leader Andrea Stewart-Cousins and State Assembly Speaker Carl Heastie, both Democrats who endorsed him, have said they are open to raising taxes.

Mamdani has said that, if elected, he would keep an open mind about paying for programs and is willing to use savings or better-than-expected tax revenues.

Here’s a look at Mamdani’s proposals.

Free child care

Mamdani’s most ambitious and expensive campaign priority is estimated to cost about $6 billion annually.

New York City’s soaring child care costs—the average annual cost of daycare for infants and toddlers in 2024 was $26,000—drives too many families from the city and forces mothers from the workforce, Mamdani says.

He wants to build on the city’s free early childhood education programs for 3- and 4-year- olds by offering no-cost daycare for every child aged six weeks to 5-years-old. There would be no income restrictions.

Hochul has said she supports universal child care, but she and Mamdani will continue to have discussions about paying for it after the election.

No major city in the U.S. offers free child care. The state of New Mexico is launching a cost-free program to all families with no income restrictions in November. But New Mexico, unlike New York City, has a dedicated funding stream for its child care program created from surplus oil and gas revenues and federal mineral leasing.

Free bus service

No-fare bus service would save the average New Yorker $2,000 a year—and cost the city under $800 million annually, Mamdani says. Free buses will speed up travel times, says Mamdani, who also wants to expand priority bus lanes to make trips faster.

The state legislature created a pilot program with free bus service for five New York City bus lines that ran for nearly one year and ended in August 2024.

The Metropolitan Transportation Authority, which runs the city’s bus service, said the pilot’s service performance had mixed results, with ridership increasing but travel speeds slowing.

A rent freeze

Mamdani has pledged to address New York City’s steep housing costs by pausing rent increases for rent-stabilized apartments for four straight years. That would cover nearly one million units and about two million residents.

The median monthly rent for a rent-stabilized apartment in New York City is estimated to reach $1,455 when Mamdani’s proposed freeze would go into effect, according to the New York Apartment Association, which represents owners of rent-stabilized apartment buildings.

The city’s mayor doesn’t have the power to unilaterally freeze stabilized rents. The New York City Rent Guidelines Board, with members appointed by the mayor, sets the rates. Mamdani, if elected, could appoint board members who would enact his freeze.

Of the nine Rent Guidelines Board members, two represent tenants, two landlords, and five advocate for the general public. Six board members are now serving under expired terms.

Current Mayor Eric Adams could reappoint those members or appoint new ones, which could complicate Mamdani’s plan.

The New York Apartment Association says a freeze could force landlords who own market-rate and rent-stabilized units to raise prices on the former to make up for losses. Some properties could wind up in foreclosure, it said.

City-owned grocery stores

Mamdani wants to create a network of city-owned grocery stores that won’t pay rent or property taxes, thereby passing savings on to shoppers, his campaign says. The stores would work with small businesses and nearby farms to buy and sell at wholesale prices.

Atlanta opened a city-owned store in September operated by a regional grocer, Savi Provisions. The rural community of St. Paul, Kan., also has a city-owned grocery.

A $30 minimum wage

Mamdani wants to raise the city’s hourly minimum wage to $30 by 2030. The current minimum wage is $16.50 and rises to $17 in January.

If such a raise were enacted, the city would have the highest minimum wage in the U.S. for all workers. Los Angeles approved a new $30 minimum wage for tourism workers by 2028. The national minimum wage is $7.25. Cuomo supports raising the minimum wage to $20 in New York City.

The state legislature sets minimum-wage laws, but the Mamdani campaign says it thinks the New York City Council has the authority to pass a local law raising the wage.

This article will be updated as news develops.

Write to Joseph De Avila at joseph.deavila@wsj.com