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 easiest way to judge a mutual fund's quality over time is by analyzing its performance, diversification, and fees. Using the Zacks Mutual Fund Rank of over 19,000 mutual funds, we've identified three outstanding mutual funds that are ideally suited to help long-term investors pursue and achieve their retirement investing goals.

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 Brandes International Small Cap Equity A (BISAX Quick QuoteBISAX - Free Report) . BISAX is a Non US - Equity option, focusing their investments acoss emerging and developed markets, and can often extend across cap levels too. This fund is a winner, boasting an expense ratio of 1.36%, management fee of 0.95%, and a five-year annualized return track record of 11.56%.

Columbia Small Cap Value II Class R5 (CRRRX Quick QuoteCRRRX - Free Report) : 0.87% expense ratio and 0.83% management fee. CRRRX is a Small Cap Value fund, and these funds are known for investing in companies with market caps under $2 billion. CRRRX, with annual returns of 8.29% over the last five years, is a well-diversified fund with a long track record of success.

AB Growth & Income I (CBBIX Quick QuoteCBBIX - Free Report) : 0.64% expense ratio and 0.55% management fee. CBBIX is a part of the Large Cap Value category, and invests in equities with a market capitalization of $10 billion or more, but whose share prices do not reflect their intrinsic value. The fund is mainly invested in equities, has a long reputation of salutary performance, and has yearly returns of 9.9% 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.