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.

Hartford Stock HLS IA (HSTAX Quick QuoteHSTAX - Free Report) : 0.51% expense ratio and 0.48% management fee. HSTAX 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. HSTAX has achieved five-year annual returns of an astounding 13.01%.

AMG Frontier Small Cap Growth Z (MSSYX Quick QuoteMSSYX - Free Report) : 0.9% expense ratio and 0.7% management fee. MSSYX is a Small Cap Growth mutual fund and tends to feature small companies in up-and-coming industries and markets. With yearly returns of 14.67% over the last five years, MSSYX is an effectively diversified fund with a long reputation of solidly positive performance.

Fidelity Blue Chip Growth (FBGRX Quick QuoteFBGRX - Free Report) : 0.78% expense ratio and 0.65% management fee. FBGRX 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 16.45% 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.