Earnings and membership soared at Washington area credit unions in 2011, fueled by a surge in consumer interest amid the anti-bank sentiment that swept the country last fall.

Assets at locally based institutions jumped 13.4 percent to $89 billion in 2011, while membership rolls swelled 15 percent to 7 million, according to data from the National Credit Union Administration. Consumer lending also grew over the past 12 months, reaching $60.1 billion by year-end, up 10.1 percent over 2010.

Meanwhile, return on average assets, a key measure of profitability, was 0.92 percent for the region, compared with 0.79 percent the prior year. Credit unions typically strive for a return of at least 1 percent.

Some local financial cooperatives recorded tremendous growth. Take Fairfax-based Apple Federal Credit Union, which increased deposits 20 percent to $1.2 billion for the 12 months ending in December. The institution, which serves the education community, added seven branches for a network of 26 locations, catering to its 145,711 members, a 27.8 percent increase over 2010.

With its abundance of government workers, the Washington area is home to some of the nation’s largest credit unions by assets, which typically boosts returns. Even without giants such as Navy Federal Credit Union or Pentagon Federal Credit Union, the region still scored substantial gains.

“People have been looking for banking alternatives, and the fees issues at large banks brought heightened attention on credit unions in the fourth quarter,” said John Bratsakis, head of the Maryland & D.C. Credit Union Association. “If you analyze member growth just in Q4, it would be almost 2.5 percent.”

Credit unions across the country added 398,000 new members in the fourth quarter alone, according to the NCUA. Many signed up following Bank Transfer Day on Nov. 5, when consumers were encouraged to move their money out of big banks to avoid fees.

Despite a decline in the overall number of federally insured credit unions from 7,339 to 7,094, the industry added 1.3 million members for the year. Consumer lending nationwide crept up 1.2 percent over 2010 to $571.5 billion by year-end 2011. Nearly two thirds of that growth occurred in the fourth quarter.