There is never a wrong time to invest in mutual funds for retirement. So, if you're still looking for the best mutual funds, the Zacks Mutual Fund Rank can be a great guide.

The best way to shortlist great mutual funds is to ensure solid performance, diversification, and low fees. Some are better than others, but utilizing the Zacks Mutual Fund Rank, we have identified three mutual funds that could be solid additions to one's retirement portfolio.

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

Hood River Small Cap Growth Institutional (HRSMX Quick QuoteHRSMX - Free Report) : 1.05% expense ratio and 0.9% management fee. HRSMX is a Small Cap Growth mutual fund and tends to feature small companies in up-and-coming industries and markets. HRSMX has achieved five-year annual returns of an astounding 13.64%.

Hartford Dividend & Growth R3 (HDGRX Quick QuoteHDGRX - Free Report) : 1.32% expense ratio and 0.6% management fee. HDGRX 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 10.9% over the last five years, HDGRX is an effectively diversified fund with a long reputation of solidly positive performance.

MFS Mass Investors Growth Stock A (MIGFX Quick QuoteMIGFX - Free Report) : 0.7% expense ratio and 0.33% management fee. MIGFX 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. The fund is mainly invested in equities, has a long reputation of salutary performance, and has yearly returns of 15.65% over the last 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.