A seven-figure nest egg is achievable if you start early and stay disciplined. By Andrea Browne Taylor, Online Editor May 14, 2016 Building a million-dollar nest egg is a popular goal. The trick, of course, is figuring out how to reach seven figures by retirement. You don’t need to win the lottery or inherit a fortune to get there. All you really need is time, discipline and a 401(k) account.See Also: 10 Reasons You'll Never Be Rich Employer-provided 401(k) plans are good deals for aspiring millionaires. Contributions are pretax, which lowers taxable income. Annual returns get a boost because you don’t pay taxes on the money until you start making withdrawals. As a bonus, many employers match a portion of workers’ contributions. To hit the million-dollar mark, you need to start early. A 30-year-old making $60,000 and contributing 3% a year will save about $367,000 by age 65. But bump up 401(k) contributions to 10% of your salary, and you’ll have $1.2 million after 35 years. (Estimates assume a 3% annual raise and a 7% rate of return.) The contribution limit to a 401(k) is $18,000 a year. But if you’re 50 or older, the maximum jumps to $24,000. Take a look at nine more ways to make $1 million.