U.S. banks have collected a record $7.5 trillion in deposits as customers feel reassured by government support. But the largest banks are also watching in frustration as longtime clients spread their business — and their deposits — among multiple banks.

Consider Ted Feight, who plans to move most of his business away from what was once National City Corp., which PNC Financial Services Group Inc. bought in December, after doing business with the Cleveland banking company for 25 years.

As president of Creative Financial Design in Lansing, Mich., he has told some financial planning clients to do the same — especially those who hold more than $250,000, the limit for government insurance.

He watched the Ohio banking company crumble last year under bad loans and has now grown nervous about its sale to Pittsburgh's PNC. "I used to take clients there," Feight says, "whereas now I'm taking clients away from them."

PNC spokesman Fred Solomon said the company has "gained back more than $2 billion in deposits from National City customers since January."

"This is our eighth acquisition in the past five years," he said, "and we have a successful track record of retaining more than 90% of the customers."

A year ago, people placed 44% of their financial business with their primary bank, according to the Mercatus consulting firm. They now put only about one-third of their business at their main bank and report being frustrated by failed banks, bonuses for bailed-out bankers and rising account fees at government-supported banks.

The awkward coincidence is that customers are pouring record levels of cash into reserve accounts at the biggest banks. Domestic U.S. deposits grew nearly $500 billion, to a record $7.5 trillion, during the year ended in March, according to the Federal Deposit Insurance Corp. And they appear to have kept growing since.

Crowds of investors sold assets for cash last year as markets tumbled. And more recently, a renewed focus on savings has helped swell deposits further.

But overflowing deposits do not necessarily lead to big profits since big banks must cover hefty fixed costs for buildings, computers and layers of full-time staff. The broad surge in deposits and new accounts can also disguise an underlying dynamic in which big banks merely trade disaffected customers. "All those new accounts have to come from somewhere," said John Philpott, the general manager of S1 Enterprise, which works with banks.

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