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.

Here are the funds that have achieved the Zacks Mutual Fund Rank #1 (Strong Buy) and have low fees.

Bridgeway Small Cap Value N (BRSVX Quick QuoteBRSVX - Free Report) has a 0.85% expense ratio and 0.61% management fee. BRSVX is a Small Cap Value mutual fund option, which typically invest in companies with market caps under $2 billion. With yearly returns of 10.1% over the last five years, this fund clearly wins.

Fidelity Advisor Equity Growth Z (FZAFX Quick QuoteFZAFX - Free Report) . Expense ratio: 0.6%. Management fee: 0.53%. FZAFX is a Large Cap Growth mutual fund, and these funds invest in many large U.S. firms that are projected to grow at a faster rate than their large-cap peers. This fund has managed to produce a robust 15% over the last five years.

Deutsche Latin America Fund S (SLAFX Quick QuoteSLAFX - Free Report) is an attractive large-cap allocation. SLAFX 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. SLAFX has an expense ratio of 1.21%, management fee of 1%, and annual returns of 13.22% over the past 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.