Things don't always work out as we planned. If your financial plan assumes that you'll retire at a certain age, but something forces you into retirement sooner, you could end up running short of money. And don't think that it can't happen to you -- the Transamerica Center for Retirement Studies discovered in a recent retiree survey that 60% of the respondents had retired earlier than they'd planned.

Why you might retire early

If you were laid off at age 60, what are the odds that you'd be able to find another job? Unfortunately, they're probably pretty slim. According to the Transamerica Center survey, two-thirds of those who retired early did so because of employment-related reasons. Health problems were the second most commonly cited reason, while only 12% of those who retired early did so because they had more money than they'd expected and could afford it.

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Planning for disaster

Given the likelihood that some event may force you to retire earlier than you'd expected, it's important to work the possibility into your retirement planning. This doesn't mean shifting your retirement plan so that you can retire at age 60. It means making contingency plans so that even if you do have to retire early, you'll be able to make ends meet until you hit your planned retirement date and your prepared sources of income become fully available.

For example, the age at which you claim your Social Security benefits has a significant impact on how much money you get. Claiming your benefits as early as possible, at age 62, results in a permanently reduced monthly check. Waiting to claim your benefits until after full retirement age makes you eligible for delayed retirement credits that will increase your benefits over the base amount. So if you're forced by some crisis to retire before full retirement age, being able to get by on other sources of income for a while so that you can wait to claim Social Security can improve your future income prospects.

Financing an early retirement

The best way to plan for the unexpected is to work some leeway into your retirement planning. For example, let's say that you spend some time with a retirement calculator and figure out that if you have $800,000 in retirement savings by age 65, you'll be able to cover your retirement expenses. In that case, $800,000 is not the best savings goal to set because it requires everything to go just right -- you retire exactly when you planned to, you don't discover any new retirement expenses, and you get the returns you wanted on your retirement investments. You'd be much better off shooting for a goal of $1 million in your retirement savings accounts by age 65. This higher goal gives you a lot more margin for error (and for the unexpected monkey wrenches that life can throw at you).

Saving consistently

Of course, the best retirement saving goal in the world won't help if you don't actually save the money that your plan calls for. Unfortunately, life's unexpected crises don't wait until retirement age to appear: A sudden, large and unexpected expense, or an unfortunate drop in income, can make saving for retirement suddenly challenging.

To protect yourself and your retirement plan from such crises, make sure that you set up a well-funded emergency savings account. Having plenty of cash tucked away to help you through these situations means that you won't have to cut back on retirement savings or (even worse) dip into those savings early.

Finally, the older you get, the more important it is to stay debt-free. Having little to no debt can make the difference between being able to struggle through an early retirement and running out of money. Again, an emergency savings account can be extremely helpful in giving you a source of funding aside from high-interest credit cards. Who knows, you may even end up among the 12% who were able to retire early because they had plenty of dough.

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