The week that rocked online trading: everything we know about brokers' rapid-fire moves to slash commissions

• The business of investing and trading online is undergoing an industry-wide shift, with many big brokerages sending their commissions to zero as competition mounts.
• Interactive Brokers, Charles Schwab, TD Ameritrade, and E-Trade all moved to eliminate fees for US-listed trades in late September and early October, in turn wiping out huge chunks of the companies' market caps.
• That's renewing speculation about consolidation across the industry.
• Business Insider regularly takes our readers inside the major online brokerages. You can read our latest by subscribing to BI Prime.

Interactive Brokers. Charles Schwab. TD Ameritrade. E-Trade.

In late September and early October, many big brokerages said they would eliminate online trading commissions for US stocks and ETFs in what felt like one fell swoop. The announcements rocked the companies' shares and renewed speculation about consolidation in the industry. And many investors and analysts are trying to guess who will cut next, while at least one startup is actually looking to pay for trades.

Several drivers are morphing these firms and influencing the choice to dump fees. Legacy brokers and big banks alike are rushing to compete with digital entrants for younger users. Meanwhile, US interest rates are falling at a faster clip than analysts had earlier expected for the rate-sensitive bunch.

Business Insider is reporting and analyzing these developments at a crucial moment for the industry. We broke down the drama unfolding in the online trading, wealth management, and discount brokerage arena.

Broker wars escalate

October 3 -The SEC's markets guru just praised brokers for slashing commissions - but warned they still need to do what's best for investors

October 3 - Charles Schwab, E-Trade, and TD Ameritrade have seen a combined $18 billion in market value erased as the brokerage-fee war has ramped up

October 2 - E-Trade and 3 other big brokers have axed the fees completely in the past week. Here's how Fidelity responded when we asked about online commissions.

October 2 - Charles Schwab on Charles Schwab: The founder explains why the firm just axed commissions as broker wars reach a fever pitch

October 2 - TD Ameritrade becomes the latest broker to eliminate fees - and its free stock trades will be available before Charles Schwab's

October 1 - Charles Schwab says it will cut online stock and ETF fees to zero - and all the major brokers are getting clobbered

September 30 - The former CEO of a high-speed-trading firm is taking aim at Robinhood with a fintech startup that wants to pay you to trade

September 26 - Interactive Brokers announces commission-free trades on online US stock, ETF trades

September 24 - JPMorgan is taking aim at apps like Robinhood by quietly rolling out options trading to select You Invest customers

More brokerage and robo news

September 18 - Charles Schwab is losing a prominent markets analyst as the discount broker gears up to cut 600 jobs

September 18 - 2 senior executives are now out at Charles Schwab as the discount broker prepares to cut 600 jobs

September 13 - Wealthfront's CFO says the roboadviser is already acting like a public company. That comes as it grabs assets in a crowded, competitive market.

September 13 -Jack Dorsey's Square is reportedly testing a free stock-trading service that would rival Robinhood

August 16 - Rivals E-Trade and TD Ameritrade had CEO shakeups within weeks of each other. The departures come as competition ratchets up among e-brokers.

July 23 - Charles Schwab's retail head and marketing chief are out - and the firm's still figuring out what's next

July 22 - Robinhood, the no-fee stock trading app, just announced a giant-size $323 million round of funding, making it worth over $7 billion

July 17 - Charles Schwab is experimenting with Netflix-style pricing. It's the clearest example yet of finance trying to imitate Silicon Valley.

July 2 - The inside story of how Robinhood, a $6 billion investing app for millennials, blew a huge launch so badly that Congress got involved

April 26 - $1.2 trillion brokerage TD Ameritrade is developing a Netflix-like recommendation engine in a bid to win investor attention

March 27 - A fintech entering the crowded wealth management space just nabbed nearly $9 million in funding from the VCs that backed Venmo, Monzo and Acorns

March 18 - For the CEO of the firm backing robos like Betterment and Stash, the future of managing money could be more like ordering dinner from a restaurant

February 8 - SoFi held talks to acquire a fintech company backing some of the hottest robo advisors as it eyes expansion beyond its lending roots

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