We're not a country that's fond of delayed gratification. (Take a gander at personal-debt statistics if you're curious about the Joneses' Visa bill.) But when it comes to retirement savings, ignore the temptation to take an early dip -- even when Uncle Sam allows it. In this case, resistance is fruitful.

Perhaps you've eyed your IRA savings when facing higher education costs. Or maybe you're a first-time homebuyer who needs a loaner to cover some of your costs. Perhaps your family has been sacked with extremely high, unreimbursed medical bills that you can cover only with money earmarked for retirement. For those with limited resources, dipping into IRA money early is the only way to get to college, become a homeowner, or cover catastrophic medical expenses.

In any other situation when you might be tempted to borrow money from your IRA before age 59 1/2 -- say, a sale at Coach (NYSE:COH) or an itch for a gadget that got great reviews on CNET (NASDAQ:CNET) -- don't do it. The price you ultimately pay is too steep.

Take, for example, Jim, who invested $2,000 in a Roth IRA seven years ago. Earning the stock market's average returns, today his balance is $3,500. When his brokerage account statement arrives, Jim doesn't see retirement dreams; he sees dollar signs. His neighbor is selling a really hot car that -- like a sign from above -- is going for exactly $3,500. Jim cashes out his IRA -- both his original $2,000 contribution and his $1,500 in earnings -- so he can get behind the wheel by the weekend.

However, Jim has a problem. He still can't afford the car even though he thought he had it covered. After paying taxes on his Roth earnings of $1,500 at his marginal tax rate (let's say that he's in the 28% tax bracket) as well as shelling out a 10% early withdrawal penalty, Jim's $3,500 Roth becomes a pipsqueak $2,900.

Had Jim been able to resist the new ride, or been able to come up with the money without touching his retirement funds, he would have been a lot better off. Had he just let his IRA ride it out for the next 30 years (at the stock market's average annual returns), it would have been worth more than 20 grand.

Sometimes resistance is fruitful.

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