The city government could save millions of dollars by implementing voting by mail, moving jury duty to the summer for teachers, or even taxing breast implants and face-lifts, according to an Independent Budget Office report that offers 63 ways to help close a budget gap the IBO estimates will be $3.1 billion in 2009.

The IBO, a nonpartisan organization that analyzes the city’s fiscal situation, says the city could raise about $65 million in revenue by subjecting cosmetic surgery and procedures to the same sales tax as consumer goods. The report, released yesterday, warns that such a move could face opposition, as some New Yorkers will argue that surgery is “vital to improving self-esteem and general quality of life.”

Voting by mail would save an estimated $7 million by doing away with voting machines and poll workers, the report says, and having public school teachers serve on juries after the school year ends would save $3 million in substitute teacher costs. Requiring firefighters and police officers, who now can retire with full benefits after 20 years of service, to be at least 50 before they collect their pension would save millions of dollars more. And raising the personal income tax of New Yorkers making more than $125,000 a year could boost revenues $366 million, according to the report.

The IBO’s suggestions came as the city comptroller, William Thompson Jr., said the economic environment ahead looks grim, although New York City posted a higher growth rate than rest of the nation last quarter, 1.1% versus 0.6%.

“A number of signs point to trouble ahead,” Mr. Thompson said in a statement yesterday. He warned that New York’s economic reliance on Wall Street means a stock market downturn would push unemployment up in the city.