Las Comisiones Ocultas que Nadie te Dice: ECN y Routing Fees
The Hidden Fees Nobody Tells You About: ECN and Routing Fees
Por Mario Maldonado · Lectura: 8 min By Mario Maldonado · Read time: 8 min
Las comisiones ECN y routing fees son cargos por acceder a la liquidez de los exchanges y pueden sumar $5–$20 por operación en cuentas activas. Ignorarlos convierte estrategias rentables en estrategias perdedoras. Lo que raramente calculan correctamente son todos los costos que se comen esa ganancia antes de que llegue a su cuenta. En mi experiencia, muchos traders que creen estar "ligeramente rentables" están en realidad perdiendo dinero una vez que contabilizan todos los costos de ejecución correctamente.
La Anatomía de una Comisión: Tres Capas de Costo
Cuando ejecutas un trade, no hay una sola comisión — hay tres capas distintas de costo que se acumulan:
- Comisión del broker: Lo que le pagas directamente al broker por ejecutar la orden
- ECN/Routing fee: Lo que cobra la red electrónica por la que viaja tu orden
- Regulatory fees: SEC fee y TAF fee — pequeños pero reales, cobrados por el regulador
La mayoría de los traders conocen la comisión del broker. Pocos entienden completamente las otras dos capas.
Add Liquidity vs Remove Liquidity: La Distinción que Cambia tus Costos
El concepto más importante en ECN fees es la diferencia entre agregar liquidez (maker) y remover liquidez (taker):
- Agregar liquidez: Colocas una limit order que queda en el book — no se ejecuta de inmediato. Estás agregando profundidad al mercado. El ECN te paga un rebate por esto.
- Remover liquidez: Tu orden se ejecuta contra una orden existente en el book — market order, o limit order que cruza con el best ask/bid. El ECN te cobra.
Tabla de Comparación de ECN Fees
| ECN | Add Liquidity (Rebate) | Remove Liquidity (Fee) | Notas |
|---|---|---|---|
| ARCA (NYSE Arca) | +$0.0020/share | −$0.0030/share | Muy usado en large caps |
| EDGX (Cboe EDGX) | +$0.0024/share | −$0.0030/share | Mejor rebate maker del mercado |
| BATS (Cboe BZX) | +$0.0022/share | −$0.0028/share | Buena liquidez, fee taker razonable |
| NSDQ (Nasdaq) | +$0.0015/share | −$0.0030/share | Menor rebate maker, mejor para Nasdaq nativas |
| IEX | $0.0000 | −$0.0009/share | Sin rebate pero fee muy bajo — bueno para estabilidad |
SEC Fee y TAF Fee: Pequeños pero Reales
Hay dos fees regulatorias que aparecen en tu estado de cuenta y que muchos traders nunca notan hasta que suman:
- SEC Fee (Section 31 Fee): Se cobra al vender. Actualmente ~$8.00 por cada $1,000,000 de ventas — es decir, $0.000008 por dólar de venta. En un trade de $50,000 de venta: ~$0.40. Parece trivial pero 100 trades de ese tamaño al mes = $40 mensuales solo en SEC fees.
- TAF (Trading Activity Fee): ~$0.000145 por acción vendida. En 1,000 acciones: $0.145 por trade.
La Fórmula del Costo Real de Ida y Vuelta
La comisión se multiplica por 2 porque se paga en entrada y salida
Comisión broker DAS ($0.005/share): $5 entrada + $5 salida = $10.00
ECN add en entrada (EDGX): −$0.0024 × 1,000 = −$2.40 (recibes rebate)
ECN remove en salida (EDGX): $0.0030 × 1,000 = $3.00
TAF fee (salida): $0.000145 × 1,000 = $0.15
SEC fee (sobre $5,000 venta): $0.000008 × $5,000 = $0.04
TOTAL: $10.00 − $2.40 + $3.00 + $0.15 + $0.04 = $10.79
Sin rebate (todo market orders):
$10.00 + $3.00 + $3.00 + $0.15 + $0.04 = $16.19
Diferencia: $5.40 por trade. En 200 trades al mes = $1,080 extra solo por routing strategy.
Tabla de Estructuras de Comisión por Broker
| Broker | Modelo | Costo por Acción | Mínimo/Trade | Tipo de Trader |
|---|---|---|---|---|
| DAS Trader Pro | Per-share | $0.004-$0.005 | $1.00 | Day trader activo |
| Lightspeed | Per-share | $0.0045 | $1.00 | High-volume traders |
| Interactive Brokers | Per-share / flat | $0.005 (IBKR Lite: gratis) | $1.00 | Versátil |
| Robinhood | PFOF (cero visible) | $0.00 visible | $0.00 | Inversor casual |
| Webull | PFOF (cero visible) | $0.00 visible | $0.00 | Inversor casual |
El Umbral de Rentabilidad: Supera Tus Costos Primero
Antes de hacer un centavo de ganancia, debes cubrir todos tus costos de ejecución. Esto tiene una implicación directa en el mínimo movimiento necesario para justificar un trade:
Con $16 de costo total round-trip en 1,000 acciones de $5: necesitas que la acción se mueva al menos $0.016 (1.6 centavos) solo para llegar a breakeven. Si tu target es $0.10 de movimiento, el 16% de tu ganancia potencial ya se fue en costos antes de abrir la posición.
Este cálculo previo es obligatorio para cualquier trader serio. Los costos de ejecución no son opcionales — son el precio de hacer negocios en los mercados.
When traders calculate their profitability, they typically do simple arithmetic: sale price minus purchase price. What rarely gets correctly accounted for is the full stack of execution costs that consume that profit before it ever reaches their account. In my experience, traders who believe they're "slightly profitable" are often actually losing money once all execution costs are properly calculated.
The Anatomy of a Commission: Three Cost Layers
When you execute a trade, there isn't one commission — there are three distinct cost layers that accumulate:
- Broker commission: What you pay the broker directly for order execution
- ECN/Routing fee: What the electronic network charges for routing your order
- Regulatory fees: SEC fee and TAF fee — small individually but real in aggregate
Most traders understand broker commissions. Few fully understand the other two layers, and even fewer proactively manage them.
Adding vs Removing Liquidity: The Distinction That Changes Your Cost Structure
The most important concept in ECN fees is the maker/taker distinction:
- Adding liquidity (maker): You place a limit order that rests in the book — it doesn't execute immediately. You're adding market depth. The ECN pays you a rebate.
- Removing liquidity (taker): Your order executes against an existing order — market orders, or limit orders that cross with the best ask/bid. The ECN charges you.
ECN Fee Comparison Table
| ECN | Add Liquidity (Rebate) | Remove Liquidity (Fee) | Notes |
|---|---|---|---|
| ARCA (NYSE Arca) | +$0.0020/share | −$0.0030/share | Widely used for large caps |
| EDGX (Cboe EDGX) | +$0.0024/share | −$0.0030/share | Best maker rebate in market |
| BATS (Cboe BZX) | +$0.0022/share | −$0.0028/share | Good liquidity, reasonable taker fee |
| NSDQ (Nasdaq) | +$0.0015/share | −$0.0030/share | Lower maker rebate, better for Nasdaq-native stocks |
| IEX | $0.0000 | −$0.0009/share | No rebate but very low fee — good for stability-focused traders |
SEC Fee and TAF Fee: Small but Real
- SEC Section 31 Fee: Charged on the sell side only. Currently ~$8.00 per $1,000,000 of sales = $0.000008 per dollar sold. On a $50,000 sale: ~$0.40. Trivial per trade, but 100 such trades per month = $40 monthly in SEC fees alone.
- TAF (Trading Activity Fee): ~$0.000145 per share sold. On 1,000 shares: $0.145 per trade.
The True Round-Trip Cost Formula
Broker commission DAS ($0.005/share): $5 in + $5 out = $10.00
ECN add on entry (EDGX): −$0.0024 × 1,000 = −$2.40 (you receive this)
ECN remove on exit (EDGX): $0.0030 × 1,000 = $3.00
TAF fee (exit): $0.000145 × 1,000 = $0.15
SEC fee (on $5,000 sale): $0.000008 × $5,000 = $0.04
TOTAL with strategic routing: $10.79
All market orders (no rebate optimization):
$10.00 + $3.00 + $3.00 + $0.15 + $0.04 = $16.19
Difference: $5.40 per trade. At 200 trades/month = $1,080 extra annually from routing strategy alone.
Broker Commission Structure Comparison
| Broker | Model | Cost per Share | Min/Trade | Best For |
|---|---|---|---|---|
| DAS Trader Pro | Per-share | $0.004-$0.005 | $1.00 | Active day traders |
| Lightspeed | Per-share | $0.0045 | $1.00 | High-volume traders |
| Interactive Brokers | Per-share / flat | $0.005 (IBKR Lite: free) | $1.00 | Versatile, multiple strategies |
| Robinhood | PFOF (zero visible) | $0.00 visible | $0.00 | Casual investors |
| Webull | PFOF (zero visible) | $0.00 visible | $0.00 | Casual investors |
The Profitability Threshold: Beat Your Costs First
Before earning a single dollar of profit, you must cover all execution costs. This has a direct implication for the minimum price movement needed to justify any trade:
With $16 total round-trip cost on 1,000 shares of a $5 stock: the stock must move at least $0.016 (1.6 cents) just to break even. If your target is $0.10 of movement, 16% of your potential gain is consumed by costs before you even open the position.
This pre-trade cost calculation is mandatory for any serious trader. Execution costs aren't optional — they're the price of doing business in markets. The traders who systematically undercount them are the ones who wonder why their consistently "good" trade ideas don't translate into account growth.