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Many individuals these days find themselves out of the workforce, some by choice (such as parents raising small children), others as a result of layoffs and downsizing. When people stop collecting an income, they often stop contributing to retirement savings. However, keeping up contributions, however small, can make a big difference in the total savings at retirement. And finding a suitable savings vehicle can be as much of a challenge as finding the money to put into to it. Fortunately, even if you don't earn a paycheck, it is still possible to save for retirement, and there are vehicles that can help.

The solo 401k

The solo 401k, also known as the independent 401k, is for individuals who are self-employed, either as sole proprietors, independent contractors or as members of a partnership. This vehicle is for businesses in which only the individual or the individual and his or her spouse are employees. The contributions to this type of 401k are made up of a combination of employee deferrals and employer profit-sharing. The employee deferral is capped at $17,000 for 2012 and $17,500 for 2013.

For individuals older than 50, there is an additional catch-up contribution of $5,500 for 2012 and 2013. The profit-sharing component for a sole proprietor is 20% of self-employment income reduced by 50% of self-employment taxes. The profit-sharing component increases to 25% of self-employment income (no deduction for self-employment taxes) for incorporated businesses. The total amount of contributions, deferrals and profit sharing to the plan in 2012 is the lesser of $50,000 ($55,500 including catch-up contribution) or 100% of compensation (excluding the catch-up contribution).

For example, suppose that Mary, a 33-year-old marketing manager, had a baby a few months ago and quit her full-time job to raise her child. She wants to keep her skills current and has decided to find some consulting work. If Mary earned $20,000 of income from a sole proprietorship in 2012, she could put away a total of $17,000 in employee deferrals.

Solo 401k plans must be established before Dec. 31 in order for contributions to be allowed for the following year.

The spousal IRA

Spouses who have no income and who file joint tax returns also have the option of contributing to a traditional or Roth individual retirement account as long as their spouses have taxable compensation. The maximum contribution for 2012 for either IRA is $5,000 plus an additional $1,000 for individuals older than 50. For 2013, this amount increases to $5,500 or $6,500, for those past 50.

For example, let's say Joe, 51, lost his job late last year and hasn't been able to find a new one but wants to continue to contribute toward his retirement. His wife has compensation from her job of $50,000 for 2012. Joe could contribute a total of $6,000 in 2012 to his IRA ($5,000 contribution plus a $1,000 catch-up contribution).

Keep in mind that filing status can affect the amount of allowable contributions. If Joe and his wife filed separately, he would be unable to contribute any amount to an IRA for the year because he had no taxable compensation. If they filed separately and he had compensation of only $2,000 for the year, his IRA contribution would be limited to $2,000.

Contributions to IRAs can be made up to April 15 of the following year. In other words, if you want to make an IRA contribution for 2012, you have until April 15, 2013.

Health savings accounts

A third retirement savings vehicle can be, surprisingly, a health savings account. An HSA is a tax-advantaged account available to individuals with high-deductible health plans for use in paying medical expenses. The individuals are the owners of the account. For individuals who are employed, contributions can be made by both the employer and the employee. Those who are not employed may make contributions on their own behalf.

Unlike with an IRA or 401k, where earned income is a requirement, the funds deposited into an HSA by an employee can come from savings, dividends, unemployment compensation and even welfare. In addition, there are no income limits on who can contribute, as there are with, for example, Roth IRAs. The maximum contribution for 2012 is $3,100 for an individual and $6,250 for a family. Additional catch-up contributions of $1,000 are allowed for individuals 55 or older. Individuals who contribute funds to the account receive an "above the line" deduction on their taxes.

So how does a medical savings account pertain to retirement savings? Distributions not used for medical expenses are included in income and are taxable. There is an additional 10% tax if these distributions are not due to death or disability or are withdrawn before the  individual turns 65. However, you could keep these funds in the HSA and begin withdrawing funds after age 65. At that point, you would pay tax on the distributions as you would a traditional IRA but would avoid the extra 10%. Aside from the obvious benefit of saving before tax for medical expenses, contributions to these accounts can serve as a source of income once you are retired.

Brokerage account

If you find that you have exhausted all of the previous options and still have more money you want to save for retirement, you could always make contributions to a taxable brokerage account. While the earnings won't be tax-deferred, you will be increasing the pot of money that will provide you with a source of income during your retirement.

The bottom line

As you can see, there are numerous opportunities for saving for retirement even if you are out of the workforce or working only part time or intermittently. The more pressing question is not whether there are tax-deferred vehicles to which you can contribute, but how you will manage your cash flow in order to save as much as you need to ensure a comfortable retirement.

To find the money to save, it's important to do your homework. You'll never know how much more you could have saved if you don't know what you are currently spending. Keep track of your spending for about six months and figure out which expenses can be cut down to squeeze in a little more retirement savings. Once you have figured out how much you spend and how much you can save, talk to your tax or financial adviser about which vehicles are best suited to your needs.

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