Investing in mutual funds for retirement is never too late. And the Zacks Mutual Fund Rank can be an excellent tool for investors looking to invest in the best funds.

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.

If you are looking to diversify your portfolio, consider Hennessy Cornerstone Mid Cap 30 Institutional (HIMDX Quick QuoteHIMDX - Free Report) . HIMDX is a Mid Cap Blend mutual fund, and usually features a portfolio with stocks of various styles and sizes, allowing for diversification within a strategy that focuses on mid cap companies. This fund is a winner, boasting an expense ratio of 0.98%, management fee of 0.74%, and a five-year annualized return track record of 14.31%.

Voya Growth & Income Portfolio S (ISVGX Quick QuoteISVGX - Free Report) : 0.92% expense ratio and 0.6% management fee. ISVGX 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 yearly returns of 11.67% over the last five years, ISVGX is an effectively diversified fund with a long reputation of solidly positive performance.

JPMorgan Large Cap Growth R5 (JLGRX Quick QuoteJLGRX - Free Report) : 0.53% expense ratio and 0.45% management fee. JLGRX 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. With a five-year annual return of 15.23%, this fund is a well-diversified fund with a long track record of success.

There you have it. If your financial advisor had you put your money into any of our top-ranked funds, then they've got you covered. If not, you may need to talk.