I’m trying to build a realistic cost comparison model and I’m running into the problem that every broker presents their pricing differently. Some lead with spreads, some hide commissions, and rebates make everything more complicated.
My goal is to create a simple formula that lets me calculate the actual price I’m paying per trade on OANDA, then use that same formula to compare fairly against other brokers. I want to include spreads, commissions, and rebates all in one calculation.
The issue is that OANDA’s spread changes by instrument and market conditions, their commission varies by account type, and GlobeGain rebates depend on your volume tier. So how do I make a fair comparison when all these pieces are moving?
I’ve seen people here mention tracking their trades in spreadsheets, but I’m not sure if there’s a standardized way to think about this. Is there a formula or a method that the community actually uses to see which broker is really the cheapest once you do the complete math?
Has anyone built a comparison like this that actually works in practice?
The formula is straightforward once you stop overthinking it. Real cost per lot equals average spread in pips plus commission in pips minus rebate in pips. Use your actual trading data, not broker estimates. Pull your last 20 trades on OANDA, calculate the average entry and exit spread you paid, add the commission, subtract your rebate. That’s your real average cost per lot. Do the same for another broker. Whichever has the lower number wins on cost. The key is using your actual trading times and instruments, not headline figures. If you scalp EUR/USD at 2am, spreads are different than London open. Build the model around your specific trading patterns, not theoretical scenarios. Most traders find that when they do this honestly, the cost difference between top-tier brokers is under 1 pip per lot. Execution quality matters more than saving 0.1 pips.
I built this exact spreadsheet a couple years ago. Here’s what actually works.
I log five columns. Instrument, entry spread in pips, exit spread in pips, commission, rebate. Then I have a formula that adds entry spread plus exit spread plus commission minus rebate. That gives me real cost per round trip.
I do this for 10 sample trades on each broker I’m comparing. After 10 trades per broker, a pattern emerges. You see which one actually costs less for your trading style.
The rebates matter, but they’re usually smaller than people think when you do the actual math. On my volume tier with GlobeGain on OANDA, I get about 0.4 pips back. That helps but doesn’t change the decision.
What changed my decision was execution quality. OANDA filled me at my requested price more often than competitors. That 0.1-0.2 pip difference in real execution beat out 0.3 pips in lower spreads elsewhere. Build the cost model, but don’t ignore execution.
The simplest approach I’ve found is to pick your most common instrument and account type, then calculate the average total cost across five recent trades on each broker.
I track spread paid at entry, spread paid at exit, any commission, and subtract the rebate. Add those together and divide by trades. That gives you an average real cost per trade.
When I did this comparing OANDA to FP Markets, OANDA came out slightly cheaper for my trading. But it was close enough that other factors like platform feel and support quality tipped the decision.
The rebates do help bring costs down, but they’re not a game-changer. They matter more when you’re trading high volume.
Log 10 trades per broker. Calculate spread plus commission minus rebate on each. Average them. Compare.
Real cost per trade equals entry spread plus exit spread plus commission minus rebate.