The funds in our "Magnificent Retirement Mutual Funds" list are some of the top-performing, best managed funds available. If you're already invested in them, congratulations! If you're not, don't worry - it's never too late to start getting the advantages of these outstanding funds for your retirement.

Great performance, diversification, and low fees: it's a pretty simple formula for a great mutual fund. Some are better than others, but utilizing our Zacks Rank, we have identified three mutual funds that would make great additions to long-term investors' portfolios.

Let's take a look at some of the highest Zacks Ranked mutual funds with the lowest fees.

Fidelity Trend Fund (FTRNX Quick QuoteFTRNX - Free Report) has a 0.63% expense ratio and 0.46% management fee. FTRNX is a Global - Equity mutual fund investing in bigger markets like the U.S., Europe, and Japan; these kinds of funds aren't limited by geography. With yearly returns of 15.69% over the last five years, this fund clearly wins.

JPMorgan Tax Aware Equity C is a stand out amongst its peers. JPECX is part of the Large Cap Blend section, and these mutual funds most often invest in firms with a market capitalization of $10 billion or more. By investing in bigger companies, these funds offer more stability, and are often well-suited for investors with a "buy and hold" mindset. With five-year annualized performance of 10.31%, expense ratio of 1.45% and management fee of 0.35%, this diversified fund is an attractive buy with a strong history of performance.

AB Small Cap Growth A (QUASX Quick QuoteQUASX - Free Report) . Expense ratio: 1.14%. Management fee: 0.75%. Five year annual return: 12.86%. QUASX is a Small Cap Growth mutual fund building their portfolio around stocks with market caps under $2 billion and large growth opportunities.

These examples highlight the fact that there are some astonishingly good mutual funds out there. If your advisor has you in the good ones, bravo! If not, you may need to have a talk.

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.