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 learn about some of Zacks' highest ranked mutual funds with low fees you may want to consider.

Black Oak Emerging Technology Fund (BOGSX Quick QuoteBOGSX - Free Report) : 1.03% expense ratio and 0.74% management fee. With a much more diversified approach, BOGSX--part of the Sector - Tech mutual fund category--gives investors a way to own a stake in the notoriously risky tech sector. BOGSX has achieved five-year annual returns of an astounding 12.96%.

Buffalo Small Cap Fund (BUFSX Quick QuoteBUFSX - Free Report) is a stand out amongst its peers. BUFSX is a Small Cap Growth mutual fund building their portfolio around stocks with market caps under $2 billion and large growth opportunities. With five-year annualized performance of 11.72%, expense ratio of 1% and management fee of 0.85%, this diversified fund is an attractive buy with a strong history of performance.

AQR Large Cap Momentum Style R6 (QMORX Quick QuoteQMORX - Free Report) : 0.3% expense ratio and 0.25% management fee. QMORX 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 a five-year annual return of 9.05%, this fund is a well-diversified fund with a long track record of success.

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.