What “raw spread” means (and the first common misunderstanding)
A raw spread broker is commonly understood as a provider model where you see a spread that is described as “raw,” instead of a markup being bundled directly into the displayed spread. In practice, the total cost you experience can still include other components such as commissions and execution-related effects.
A frequent mistake is assuming “raw spread” means “no markup” or “cheapest possible trading.” It only describes a presentation or cost structure; it does not eliminate trading costs, and it does not guarantee better outcomes.
Mechanics: where costs and numbers can go wrong
A second mistake is mixing stable mechanics with variable factors.
Stable mechanics (what you can treat as assumptions):
- The idea that your order is filled at an execution price affected by liquidity and your order type.
- A commission model (if present) that you should be able to compute from stated terms.
- The notion of a “spread” as the difference between bid and ask quotes.
Variable factors (what changes):
- Market conditions, including liquidity and volatility.
- The gap between quoted prices and actual fill prices (often wider during fast moves).
- Execution quality differences across order timing and market hours.
How this leads to errors: people may calculate “effective cost” using the displayed raw spread, while ignoring commissions or assuming fills occur at the displayed mid-price. Another common error is treating historical relationships between spreads and outcomes as if they are stable; relationships can change.
Material limitation and failure mode: quoting vs filling
One material failure mode is believing that the “raw spread” you observe is the spread you always trade through. Quotes are not fills. Even with the same quoted spread, your actual entry and exit prices can differ due to slippage, partial fills, or order handling.
Example (with explicit assumptions):
- Assume you place a market order when bid-ask quotes are 1 pip apart.
- You also assume your broker fills instantly at the best available price.
- If either assumption is wrong (for example, liquidity is thin at that moment), your effective spread becomes wider than the quoted spread.
The key point is not the specific numbers, but the logic: you need to separate quote observations from execution reality.
Costs-features checks: neutral ways to verify your assumptions
A neutral check helps you independently evaluate “raw spread” claims without predicting results.
- Compute total expected cost using your own assumptions. Combine commission (if any) with an estimate of effective spread, not just the displayed raw spread.
- Stress the assumption “fill at quote.” Review how market conditions could change fills. If your calculation assumes perfect fills, treat it as a best-case model.
- Avoid single-metric conclusions. A low displayed spread does not automatically mean lower total cost when other fees or execution effects exist.
Relevant limitations and risks to keep in mind
Even if you correctly understand the mechanics, there are risks that “raw” models cannot remove:
- Market risk: price can move against your position regardless of cost structure.
- Execution uncertainty: spreads and fill prices are not fully controllable.
- Jurisdiction and provider differences: exact terms vary by jurisdiction and provider, so you must verify the current legal and fee documents relevant to your situation.
If you want to verify further, focus on what you can test or calculate from stated terms: commission schedules, order types, and execution explanations.
Verification checklist and next question to ask
To avoid the most common mistakes, compare what you are seeing (quotes) with what you can actually verify (your stated commission and execution terms).
Next question: when you model “cost,” are you using effective spread and commission for your own assumptions about order type and fill behavior—or only the displayed raw spread?