Our "Magnificent Retirement Mutual Funds" list includes some of the best managed and best performing funds around. If you're already invested in these, congratulations! But if you're just now discovering them, don't worry. When it comes to your retirement, it's never too late to start investing in the best.

The easiest way to judge a mutual fund's quality over time is by analyzing its performance, diversification, and fees. Using our Zacks Rank of over 19,000 mutual funds, we've identified three outstanding mutual funds that are ideally suited to help long-term investors pursue and achieve their retirement investing goals.

Let's learn about some of Zacks' highest ranked mutual funds with low fees you may want to consider.

T. Rowe Price Global Stock (PRGSX Quick QuotePRGSX - Free Report) : 0.81% expense ratio and 0.64% management fee. PRGSX is a Global - Equity mutual fund. These funds invest in large markets like the U.S., Europe, and Japan, and operate with very few geographical limitations. With annual returns of 14.2% over the last five years, this fund is a winner.

Dreyfus US Equity Fund Y (DPUYX Quick QuoteDPUYX - Free Report) : 0.8% expense ratio and 0.75% management fee. DPUYX is a Large Cap Growth option; these mutual funds purchase stakes in numerous large U.S. companies that are expected to develop and grow at a faster rate than other large-cap stocks. DPUYX, with annual returns of 11.77% over the last five years, is a well-diversified fund with a long track record of success.

American Funds Washington Mutual Investors 529F (CWMFX Quick QuoteCWMFX - Free Report) . Expense ratio: 0.42%. Management fee: 0.23%. Five year annual return: 10.77%. CWMFX is a Large Cap Value mutual fund, which invests in stocks with a market cap of $10 billion of more, but whose share prices do not reflect their intrinsic value.

So, there you have it - if your advisor has you invested in any of our "Magnificent Retirement Mutual Funds," they are certainly earning their keep. If not, you may want to look elsewhere.

Do You Know the Top 9 Retirement Investing Mistakes?

Investing in underperforming mutual funds is just one of the key errors that can derail your retirement plans.

To learn more, read our just-released report: 9 Retirement Mistakes You Need to Avoid.