Cuando Robinhood fue pionero en el trading de acciones sin comisiones, cambió la industria para siempre. Today, nearly every major platform offers zero-commission trades on stocks and ETFs. But "commission-free" isn't the same as "free." And the difference can cost you more than commissions ever did.
Pago por flujo de órdenes: el impuesto oculto
Pago por flujo de órdenes (PFOF) is the practice of selling your trade orders to high-frequency trading firms (market makers) who then execute your trades. The market maker profits from the bid-ask spread and pays the broker for the privilege of seeing your orders first.
"If you're not paying for the product, you are the product. In trading, your orders are the product being sold."
In 2025, major brokers earned a combined $3.4 billion from PFOF. That's money that ultimately comes from the trading community through slightly wider effective spreads. Our testing quantified this: on a typical 100-share order of a $50 stock, PFOF-reliant platforms delivered execution prices that were $0.02–$0.04 per share worse than direct-routing platforms like Interactive Brokers.
Spread Markups on Crypto
Crypto trading on stock-focused platforms comes with hidden spread markups that dwarf what you'd pay on a dedicated crypto exchange. We tracked the effective spread (the difference between the price shown and the price you actually pay) across platforms:
The most successful traders combine knowledge with the right tools. Focus on understanding the fundamentals before committing real capital.
- Dedicated crypto exchanges (Coinbase Pro, Kraken): 0.1–0.5% effective spread
- Traderise: 0.3–0.6% effective spread
- Robinhood Crypto: 0.4–1.2% effective spread
- Webull Crypto: 0.5–1.5% effective spread
- SoFi Crypto: 1.0–1.5% effective spread
On a $1,000 crypto trade, the difference between the tightest and widest spread could cost you $10–$15. Multiply that across a year of active trading and you're paying more than you ever did in stock commissions.
Margin Rate Roulette
Margin interest rates have risen sharply with interest rates, but the range between platforms is striking:
- Interactive Brokers: 5.83% (benchmark + 1.5%)
- Traderise: 6.5%
- Fidelity: 8.325%
- Robinhood Gold: 8.0%
- Webull: 7.99% (above $25K balance)
For a $10,000 margin balance, the difference between 5.83% and 8.325% is $249.50 per year. That's real money that doesn't show up in a "commission-free" comparison.
The Fees You Didn't Know About
Account Transfer Fees
Want to move to a better platform? Most brokers charge $50–$75 to transfer your account via ACAT. Some will reimburse this fee — Traderise and Fidelity do; Robinhood and Webull don't.
Wire Transfer Fees
Need your money fast? Wire transfers typically cost $25–$30 outgoing. ACH is free but takes 2–5 business days.
Inactivity Fees
Most major platforms have eliminated inactivity fees, but some smaller or forex-focused platforms still charge $5–$15/month if you don't trade regularly. Always check the fee schedule.
How to Minimize Hidden Costs
- Check execution quality reports. SEC Rule 606 reports reveal where your orders are routed. Platforms with high PFOF revenue may not be getting you the best prices.
- Compare margin rates before borrowing. A 2% rate difference on a $10,000 balance is $200/year.
- Use limit orders instead of market orders. This protects you from spread markup regardless of platform.
- Trade crypto on crypto platforms. If you're serious about crypto, use a dedicated exchange with transparent order books.
- Read the fine print. Every platform publishes a fee schedule. Most traders never read it. You should.
La Conclusión
Commission-free trading was a genuine revolution, but it shifted costs rather than eliminating them. The most transparent platforms — Interactive Brokers, Traderise, and Fidelity — minimize these hidden costs and are upfront about how they make money. The least transparent ones profit from your confusion. Choose accordingly.