Over half of American donors (55%) plan to maintain the same level of charitable giving in the fourth quarter, despite market uncertainty, according to a survey by the Fidelity Charitable Gift Fund, the largest donor-advised program nationally.

Charitable giving is of key interest to wealthy investors. Fidelity spokeswoman Teri Ginsburg said Center on Philanthropy at Indiana University figures showed 98% of high-net-worth individuals made charitable donations back in 2007, and their philanthropic behavior hasn’t changed.

Eight percent of donors said they’d give more than usual because need is even greater in this economy than in past years. Recent natural disasters such as the flood in Pakistan and the earthquake in Haiti have also triggered interest in donating funds.

Then there’s tax planning, which remains an important consideration in the decision to give, but it isn’t the overriding motivation for most donors. Only 31% of respondents said tax deductions are a “significant” factor in their decision to donate, and 88% of donors said they wouldn’t decrease their charitable giving due to tax increases. Back in July, another survey found that one in four advisors expected their wealthy clients to increase charitable giving in order to offset their tax obligations: At 51%, more than half of donations Fidelity received in the first nine months of 2010 were in appreciated stocks, compared to 39% last year.

Even though client demand is high, only 52% of advisors are proactively reaching out to clients, even though 63% of advisors think clients need help in this area. “Many advisors aren’t approaching clients about this,” Ginsburg said. “It’s an untapped opportunity for advisors to strengthen client relationships and grow their practices.”

Advisors who don’t offer help say it’s because clients don’t ask for help (52%), donations are a client’s personal business (44%), or that the advisor lacks the expertise to offer guidance (31%). One might cynically suggest that advisors also have little interest in their clients giving their money away, too, but Ginsburg points out that in national donor-advised funds, advisors can retain control of how their clients donations are invested.

That’s a potential selling point to clients who can’t afford to give as much this year as they’d prefer. Just under one-third of donors (30%) say they can’t give as much as they normally would due to financial limitations resulting from market volatility, and 6% said they’re holding back until the tax implications becomes clearer. However, 88% of people cutting donations in the fourth quarter said charitable giving remains a priority.