It is never too late to invest in mutual funds for retirement. As such, if you plan to invest in some of the best funds, the Zacks Mutual Fund Rank can provide you with valuable guidance.

The easiest, most reliable way to judge a mutual fund's quality over time is by analyzing its performance, diversification, and fees. The Zacks Mutual Fund Rank, which covers over 19,000 mutual funds, has helped us identify three outstanding options that are perfect for any long-term investors' portfolios that is retirement-focused.

Let's take a look at some of our top-ranked mutual funds with the lowest fees.

Fidelity Blue Chip Growth Fund (FBGRX Quick QuoteFBGRX - Free Report) has a 0.71% expense ratio and 0.63% management fee. FBGRX is a Large Cap Growth mutual fund, and these funds invest in many large U.S. firms that are projected to grow at a faster rate than their large-cap peers. With yearly returns of 13.59% over the last five years, this fund clearly wins.

Putnam Equity Income R5 (PEQLX Quick QuotePEQLX - Free Report) . Expense ratio: 0.65%. Management fee: 0.47%. PEQLX is a part of the Large Cap Value category, and invests in equities with a market capitalization of $10 billion or more, but whose share prices do not reflect their intrinsic value. This fund has managed to produce a robust 10.39% over the last five years.

Vanguard Growth & Income Admiral (VGIAX Quick QuoteVGIAX - Free Report) . Expense ratio: 0.22%. Management fee: 0.21%. Five year annual return: 11%. VGIAX 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.

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.