Trading Commissions Explained: What You Actually Pay
Commissions are evolving from simple flat fees to complex per-share and tiered pricing models. Understand how commission structures work and which model saves you the most.
Key Takeaways
- ✓Commission structures vary widely: flat-rate, per-share, tiered volume-based, and zero-commission models each suit different trading styles.
- ✓Zero-commission is not always cheapest — active traders may benefit more from transparent per-share pricing with superior execution.
- ✓Options commissions typically consist of a base fee plus a per-contract charge, which can range from $0.50 to $1.50 per contract.
- ✓The most cost-effective commission model depends on your trade frequency, average order size, and the assets you trade.
Trading commissions are the fees a broker charges each time you execute a buy or sell order. For decades, commissions were the primary revenue source for online brokers and the main cost factor for individual investors. The zero-commission revolution that began in 2019 fundamentally changed this dynamic, but commissions have not disappeared — they have simply evolved into more nuanced pricing structures.
Commission Models Compared
| Model | How It Works | Best For | Example |
|---|---|---|---|
| Flat-rate | Fixed fee per trade regardless of size | Occasional investors with larger order sizes | $4.95 per trade |
| Per-share | Fixed fee per share traded | Active traders with variable order sizes | $0.005 per share (min $1) |
| Tiered volume | Fee decreases as monthly volume increases | High-volume active traders | $0.005/share at 1M+ shares/month |
| Zero-commission | No explicit commission; revenue from PFOF/spreads | Casual investors and buy-and-hold | $0 per trade |
| Flat monthly | Fixed monthly fee for unlimited trading | Very active day traders | $99/month unlimited |
The Zero-Commission Trade-Off
When Robinhood pioneered commission-free stock trading in 2014 and other major brokers followed in 2019, it was celebrated as a democratization of finance. But zero-commission is not free — the cost has simply shifted from a visible commission line item to less transparent mechanisms.
Brokers that offer zero commissions typically monetize through PFOF and wider spreads. For a casual investor making a few trades per month, the practical cost difference compared to a $5 commission broker may be only a few dollars. But for an active trader making hundreds of trades, the execution quality differences at a zero-commission broker can easily exceed what they would pay in transparent commissions at a DMA broker.
Options Trading Commissions
Options commissions are typically structured as a base fee plus a per-contract charge. This is one area where commission differences between brokers remain significant:
| Broker | Base Fee | Per Contract | Total for 10 Contracts |
|---|---|---|---|
| Interactive Brokers | $0 | $0.65 | $6.50 |
| Charles Schwab | $0 | $0.65 | $6.50 |
| Fidelity | $0 | $0.65 | $6.50 |
| Robinhood | $0 | $0.00* | $0.00* |
| E*TRADE | $0 | $0.65 | $6.50 |
*Robinhood offers $0 per-contract options trading but monetizes through PFOF and may provide inferior execution on complex multi-leg strategies. For active options traders who value execution quality, the per-contract fee at a DMA broker may represent better overall value.
How to Calculate Your Commission Cost
To estimate your monthly commission cost, multiply your expected number of trades by the commission per trade. For per-share pricing, estimate the average number of shares per trade. Consider whether you are likely to qualify for volume-based tier discounts at your expected activity level.
Use our Trading Commission Calculator at MyFastBroker to estimate your monthly costs across different brokers based on your specific trading volume and order sizes.