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 break down some of the mutual funds with the top Zacks Mutual Fund Rank and the lowest fees.

MFS Blended Research Growth Eq R6 (BRWVX): 0.42% expense ratio and 0.4% management fee. BRWVX 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. BRWVX has achieved five-year annual returns of an astounding 11.92%.

Fidelity Convertible Securities (FCVSX): 0.74% expense ratio and 0.55% management fee. FCVSX is a Convertible Bonds fund, which are unique investment opportunities because they have both fixed income and equity components, making them hybrid securities. With yearly returns of 11.02% over the last five years, FCVSX is an effectively diversified fund with a long reputation of solidly positive performance.

Red Oak Technology Select (ROGSX) is an attractive large-cap allocation. ROGSX is a Sector - Tech mutual fund, allowing investors to own a stake in a notoriously volatile sector with a much more diversified approach. ROGSX has an expense ratio of 0.94%, management fee of 0.74%, and annual returns of 11.42% over the past five years.

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.

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