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 take a look at some of our top-ranked mutual funds with the lowest fees.

If you are looking to diversify your portfolio, consider SEI Inst Mgd Tr-Small Cap Value F (SESVX). SESVX is a Small Cap Value fund, and these funds are known for investing in companies with market caps under $2 billion. This fund is a winner, boasting an expense ratio of 1.1%, management fee of 0.65%, and a five-year annualized return track record of 8.61%.

Putnam Focused Equity Y (PGILX). Expense ratio: 0.83%. Management fee: 0.6%. PGILX is a Global - Equity mutual fund, which invests their assets in large markets, leveraging the global economy. This fund has managed to produce a robust 13.98% over the last five years.

First Eagle Fund of America I (FEAIX Quick QuoteFEAIX - Free Report) . Expense ratio: 0.65%. Management fee: 0.5%. Five year annual return: 13.14%. FEAIX, an All Cap Value option, is a type of mutual fund that buys stakes in companies in all three valuation categories

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.