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.

Brandes International Small Cap Equity I (BISMX): 1.15% expense ratio and 0.95% management fee. BISMX is a part of the Non US - Equity fund category, many of which will focus across all cap levels, and will typically allocate their investments between emerging and developed markets. BISMX has achieved five-year annual returns of an astounding 9.33%.

Principal Large Cap Growth I A (PLGAX): 1% expense ratio and 0.6% management fee. PLGAX 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 yearly returns of 13.79% over the last five years, PLGAX is an effectively diversified fund with a long reputation of solidly positive performance.

American Funds Mutual Fund R6 (RMFGX). Expense ratio: 0.27%. Management fee: 0.23%. Five year annual return: 10.12%. RMFGX is a Large Cap Value mutual fund, which invests in stocks with a market cap of $10 billion of more, but whose share prices do not reflect their intrinsic value.

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.

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