Getting an apartment in New York City was supposed to be easier this summer. Because of a new law, many renters would no longer have to pay thousands of dollars to brokers that landlords had brought in to help.

For many people, that has proved true. But a New York Times analysis of 1.3 million listings on the popular rental site StreetEasy also suggests that the shift has come at a cost: Many more landlords than usual raised rents the week the law took effect in June, often by hundreds of dollars a month.

Even though higher rents are typical in the busy summer season, the median rent in the city rose in June more than would be expected, according to statistics provided by StreetEasy.

The Times’s analysis showed a spike in rent increases around June 11, when the law, the FARE Act, took effect with a simple but transformative premise: Whoever enlists a broker’s help should pay the broker’s fee, which is often thousands of dollars.

StreetEasy released a report about a month later saying that the law had not hurt the rental market. The company, which publicly supported the law in the face of fierce opposition from the real estate industry, acknowledged the surge in rent increases when The Times asked about it this week.

“There’s no free lunch,” said Kenny Lee, a senior economist at StreetEasy. “Landlords will always try to offset the additional cost by passing some of it to the renters as a higher base rent. They are not running a charity.”