By Nellie S. Huang, Ryan Ermey, Kiplinger's Personal Finance Kiplinger's Money Power

Not all investors -- or brokers -- are alike. Depending on the type of investor you are, here are the best brokers for you.

Best for exchange-traded fund investors

Firstrade slays the competition in our survey with its roster of 703 commission-free exchange-traded funds. It includes 15 of Kiplinger's favorite ETFs, including iShares Core S&P 500 (symbol IVV), Vanguard Dividend Appreciation (VIG) and Pimco Active Bond (BOND).

Best for mutual fund investors

Fidelity, Schwab and TD Ameritrade all offer customers access to more than 4,000 no-fee mutual funds on their no-transaction-fee networks. That means you pay no sales load and no fee to trade. Schwab, as it has in past years, topped the list, with 4,121 no-fee funds. It's worth noting that Fidelity has debuted the first index funds with a zero percent expense ratio.

Best for bond investors

Firstrade wins by a nose, followed by E*Trade. These firms offer their clients access to tens of thousands of corporate and municipal bonds, leading their peers in both categories.

Best robo adviser services

Schwab's Intelligent Portfolios wins. The service is free, and it offers more portfolios than any other firm. There are 43 in all, tailored to your goals, tolerance for risk and stage in life. Intelligent Portfolios has a couple of downsides: It requires $5,000 or more to start, and its most aggressive portfolio currently holds a hefty 7 percent cash position, a potential drag on returns. But according to The Robo Report, which tracks the performance of digital advisory portfolios, Schwab has achieved good results over time.

Best for active traders with high balances

Customers with deep pockets can pay $0 in commissions at Merrill Edge. If you have an active Bank of America checking account and a three-month average balance of $50,000 at Bank of America, Merrill Edge or Merrill Lynch investment accounts (singly or in combination), you can join a rewards program and qualify for no commissions on up to 30 stock and ETF trades per month. Investors with a $100,000 average balance can get 100 free trades every month.

Best for students of investing

ETrade and TD Ameritrade have made it a priority to teach and inform customers about investing, each in its own way. "Our goal is to make investing easier for people," says ETrade's Rich Messina. E*Trade caters to beginner investors with "All Star" lists of recommended ETFs, stocks and mutual funds, plus ready-to-go ETF portfolios. TD Ameritrade's website is chock full of short videos and longer online courses for investors of all experience levels. The firm also does a good job of defining and explaining key investing terms on its site, from "earnings per share" to "annual dividend yield."

(Nellie S. Huang is a senior associate editor and Ryan Ermey is a staff writer at Kiplinger's Personal Finance magazine. Send your questions and comments to moneypower@kiplinger.com. And for more on this and similar money topics, visit Kiplinger.com.)

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