Updated on July 6, 2007.

QUESTION: I'm 30 years old, self-employed and want to start my own retirement account. What are my options?

ANSWER: Younger entrepreneurs have an array of tax-advantaged retirement plans to choose from that are relatively simple and cheap to set up. The big ones to consider: the individual 401(k), the SIMPLE IRA, the SEP-IRA and the Keogh profit-sharing plan.

Which is best? That depends on several factors, including one's salary, the growth plans for the company, and whether there are additional employees involved. In short, which one is right for you depends on how much you can contribute to the account, says Gene Fairbrother, lead small-business consultant in Dallas for the National Association for the Self-Employed, a trade group. If you can't yet make a sizable contribution, think about basic options available to any individual, such as the Roth or traditional IRA, he says.

Once you're drawing a comfortable salary, however, it's time to pick an option designed specifically for the self-employed, since the contribution limits are significantly higher than the $4,000 max imposed on most traditional and Roth IRA investors. Rande Spiegelman, vice president of financial planning with the Schwab Center for Investment Research, suggests a few salary guidelines:

• If you're making $75,000 or less, take a look at the SIMPLE (Savings Incentive Match Plan for Employees) IRA. This low-cost plan allows a maximum contribution of $10,000 a year, which grows tax-deferred. It's easy to maintain, and there's no IRS filing. The simple IRA also works well for the business owner with a small group of employees, as the employer can match employees' contributions of up to 3% of annual compensation.

• If your salary falls roughly in the range of $75,000 to $230,000, consider the individual 401(k). You'll enjoy some of the highest contribution limits for the self-employed, with tax-deductible contributions of up to 20% of self-employment income. An extra bonus: As an employee of the company, you can contribute an additional $15,000, which makes the solo 401(k) that much sweeter. The maximum contribution is $45,000 in 2007 and $50,000 if you're 50 or older by year end. And it's flexible, so you can make higher contributions and rack up big tax savings when business is good, and cut back during lean years.

• If you're earning more than $230,000, think about a SEP-IRA or Keogh. Both plans allow for tax-deductible contributions of 25% of your compensation (if your business is set up as a corporation) or 20% of your self-employment income (if you're a sole proprietor), up to a maximum of $45,000 in 2007. The SEP-IRA is considered the small-business retirement plan with the easiest administration, and can be set up as late as the tax returns (even extensions) are due, so it's perfect for the time-pressed business owner. The Keogh profit-sharing plan generally requires a professional to set up, but is considered good for an employer who wants tight control over contributions and investments.

The good news is that more firms, including Fidelity Investments, Wachovia, and Siebert Financial, are focusing attention on small-business owners. Last fall, Schwab cut account-service fees on retirement plans for small business, and online brokerage Sharebuilder.com launched a 401(k) division for small employers.

One last thing: You may have heard about an increasingly popular defined-benefit plan often referred to as "solo pensions" but they're largely designed for older business owners (generally, 50 or older) who need to catch up quick on retirement savings.

For more on small-business retirement plans, click here.