So you just got a pile of cash. Here's your next move

Forget fantasies of designer clothes and luxury cars — most Americans say they have more modest plans should they ever join the ranks of millionaires.

Whether they stick to those vows is another matter.

Nearly nine in 10 consumers say if they were to suddenly earn or receive "millions," they would save or invest at least a portion of that money, according to a forthcoming TD Ameritrade survey of just over 1,000 adults. (The exact windfall amount was left to the respondents' imaginations.) Of those hopeful wealth-builders, 66 percent say they would save or invest at least half of their new wealth.

(See chart below for other ways consumers said they would use newfound wealth.)

"That's a really good indication of a culture shift," said Susan Bradley, a certified financial planner and founder of the Sudden Money Institute in Palm Beach Gardens, Florida, which helps consumers make the most of such wealth changes.

In consumers' plans for a big cash influx like a lottery win, investing usually comes in low on the list, Bradley said.

"Our experience is … people say that they would buy a house, or something house related," she said. "I have found that to be consistently true." Vacations and funding a child's education are other oft-cited top priorities.

"There's this preset notion that people will blow through unearned money," said David Lynch, a managing director and head of branches at TD Ameritrade.

It's a welcome surprise that people are more aware of the potential impact of sudden wealth for their bottom line, and that a windfall may not amount to a fast financial fix, he said. A quarter of the respondents said even with those millions, they wouldn't necessarily be set for life.

"Sometimes what you say and what you do are two different things," Lynch said. There's plenty of evidence that responsible money management can fly out the window in the face of a sudden influx of cash.

A 2012 study in the Journal of Family and Economic Issues, for example, found that 34.9 percent of inheritors saw their net worth either decline or hold steady — indicating they didn't save the money or use it to pay down debt. Along with individual tales of lottery winner financial woes, a 2010 Vanderbilt Law and Economics paper found that financially distressed Florida lottery winners were only able to postpone — not avoid — bankruptcy.

Considering what to do with hypothetical millions might actually be a smart idea.

While your odds of a big lottery win or NFL contract may be slim, sudden money isn't just limited to those kinds of extreme or unexpected windfalls, said Bradley. Selling a business, inheriting money, receiving an insurance settlement or a big bonus at work or even retirement — when all your savings suddenly become available to tap — all entail receiving a big sum of cash at once.

Ideally, consumers faced with instant wealth should take time to consider their financial and life goals before they do anything with the money, said Lynch. Consult with a financial professional to figure out the best ways to invest or save that money.

"Develop a plan," he said. "Working without a plan is just hoping to hit a goal."