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

Deutsche Science and Technology Institutional (KTCIX Quick QuoteKTCIX - Free Report) : 0.69% expense ratio and 0.45% management fee. KTCIX is part of the Sector - Tech mutual fund category that invests in technology and lets investors own a stake in a notoriously volatile sector, but with a much more diversified approach. With annual returns of 14.6% over the last five years, this fund is a winner.

GMO Quality III (GQETX Quick QuoteGQETX - Free Report) : 0.49% expense ratio and 0.48% management fee. GQETX is classified as a Large Cap Blend fund. More often than not, Large Cap Blend mutual funds invest in companies with a market cap of over $10 billion. Buying stakes in bigger companies offer these funds more stability, and are well-suited for investors with a "buy and hold" mindset. With yearly returns of 12.4% over the last five years, GQETX is an effectively diversified fund with a long reputation of solidly positive performance.

Fidelity OTC Portfolio (FOCPX Quick QuoteFOCPX - Free Report) : 0.78% expense ratio and 0.64% management fee. FOCPX 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. The fund is mainly invested in equities, has a long reputation of salutary performance, and has yearly returns of 14.01% over the last five years.

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.