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.

Brown Advisory Flexible Equity Institutional (BAFFX Quick QuoteBAFFX - Free Report) has a 0.54% expense ratio and 0.43% management fee. BAFFX is classified as an Allocation Balanced fund, which seeks to invest in a balance of asset types, like stocks, bonds, and cash, and including precious metals or commodities is not unusual. With yearly returns of 11.15% over the last five years, this fund clearly wins.

Fidelity Series Growth & Income (FGLGX Quick QuoteFGLGX - Free Report) : 0.63% expense ratio and 0% management fee. FGLGX is part of the Large Cap Blend section, and these mutual funds most often invest in firms with a market capitalization of $10 billion or more. By investing in bigger companies, these funds offer more stability, and are often well-suited for investors with a "buy and hold" mindset. FGLGX, with annual returns of 11.3% over the last five years, is a well-diversified fund with a long track record of success.

JPMorgan Large Cap Growth I (SEEGX Quick QuoteSEEGX - Free Report) : 0.68% expense ratio and 0.45% management fee. SEEGX 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 14.83% 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.