(Dow Jones) The Vanguard Group is now offering its brokerage clients commission-free transactions across its line of exchange-traded funds, and lowering the commissions they pay to trade stocks and non-Vanguard ETFs.

The lowered commissions apply to transactions conducted on Vanguard.com and those executed with the assistance of a Vanguard brokerage representative, the Valley Forge, Pa.-based asset manager said Tuesday. Most Vanguard brokerage clients will pay $2 or $7 to trade stocks and non-Vanguard ETFs, it said.

Vanguard's move comes about three months after Fidelity Investments said it would offer 25 iShares ETFs on a commission-free basis, and reduce online equity-trading commissions for all customers. Fidelity, which is in partnership with iShares, a unit of BlackRock Inc. (BLK), was taking aim at rival Charles Schwab Corp. (SCHW), which was already offering commission-free trades on eight ETFs it manages.

ETFs trade on exchanges like stocks, and investors typically pay a commission for trades, which can add up over time. More ETF providers may waive commissions in coming months as the battle for space in the marketplace continues to heat up.

Vanguard is the industry leader in ETF net cash flows this year, with an estimated $11.7 billion through April 29, and ETF assets of more than $100 billion, the company said.

"Vanguard offers a greater choice of ETFs with expense ratios that are among the lowest in the industry," Vanguard Chief Executive Bill McNabb said in a release Tuesday.

Vanguard offers 46 ETFs that seek to track various domestic and international stock benchmarks as well as broad and discrete segments of the domestic bond market. The average expense ratio of a Vanguard ETF is 0.18%, compared with the industry average of 0.52%, according to Lipper Inc.

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