Bank Transfer Day turned out to be more of an exclamation point at the end of a rallying cry. Thousands made the switch to credit unions on Nov. 5, but they came at the tail end of a transfer tsunami that had been gaining strength for a month. Banks hoping to float over that wave should get ready to batten down the hatches -- a banking survey released just before Thanksgiving shows rough seas ahead in 2012.

On stronger tides
The survey performed by consulting firm cg42 sought to determine the vulnerability of banks to their customers jumping ship. Vulnerable turns out to be the perfect word for the situation, since the study makes clear how poorly many banking customers view their banks.

Not all banks are at major risk, though. Some appear to be positioned to benefit from the woes of their competitors, should the recent fervor for community banking and credit unions fade after the New Year. The chart below shows banks' vulnerability, in billions of dollars:

Bank

Total Retail Deposits*

Customers Considering Switching

Potential Deposits in Play*

Customers Likely to Switch Within 12 Months

Projected Deposits Lost in Next 12 Months*

Wells Fargo (NYSE: WFC) $530 18% $94 9.1% $48
Bank of America (NYSE: BAC) $407 22% $88 10.3% $42
JP Morgan Chase $344 24% $83 8.9% $31
Citigroup (NYSE: C) $145 23% $33 9.8% $14
TD Bank (NYSE: TD) $131 22% $29 8.6% $11
PNC Financial (NYSE: PNC) $126 14% $18 7.4% $9
US Bancorp (NYSE: USB) $101 17% $17 7.9% $8
BB&T (NYSE: BBT) $95 15% $14 8.4% $8
Capital One $83 15% $12 9% $7
SunTrust Banks $75 14% $10 7.5% $6
Sum or Average $2,036 20% $399 8.7% $185

Source: cg42, 2010 corporate annual reports, and FDIC.  *All figures in billions.

Not-so-stormy seas after all?
While the big four could all lose substantial deposits, it's unclear how dangerous -- or likely -- this threat truly is. Fool contributor Morgan Housel points out that Wells Fargo, projected to lose $48 billion in deposits by next Thanksgiving, saw its balances grow by $41.8 billion in its most recent quarter.

I also question the projected losses, having seen some early figures from the big-bank exodus. Considering the $4.5 billion flowing into credit union coffers from 650,000 new customers, it seems that Wells Fargo alone would need to lose nearly 8 million accounts for these projections to become a reality. That, of course, assumes that all the new transfers would be roughly equivalent to the unexpectedly high average deposit of $6,293.

Pirates off the port bow
Viewing this survey as a satisfaction barometer, it's clear that some banks are serving their customers better than others. PNC has the lowest percentage of customers considering a switch, while Bank of America faces the grimmest near-term future. JP Morgan Chase, however, has slightly greater risk of losses over the long term.

All the transfers in the world, however, won't help the banks on the receiving end if no one wants loans. The odd paradox of all this dissatisfaction could be that the banks losing the most accounts could also improve their profitability the most -- as long as people remain afraid to take on more debt.

If you'd like us to keep you updated on Wall Street reform, simply send a blank email to [email protected].