MT4 vs MT5 for Prop Firm Trading

For most traders this is a mild preference. For anyone running a robot it is a hard technical decision, because an Expert Advisor written for one platform simply does not run on the other. They are not two versions of the same program, they are two different programs with similar names. In 2026 most prop firms have settled on MT5, which makes the choice easier than it used to be. Here is what actually differs, and what it means for automation.

The difference that matters most: EAs are not interchangeable

MT4 runs Expert Advisors written in MQL4. MT5 runs Expert Advisors written in MQL5. They are different programming languages, so an MT4 robot cannot be installed on MT5, and the reverse is equally true. There is no compatibility mode and no setting that fixes it.

This catches people constantly. A trader buys a robot, opens a prop account, then discovers the account is on the other platform and the file will not load. So before you buy any automation, confirm two things: which platform your firm gives you, and which platform the robot was built for. If they do not match, nothing else in this comparison matters.

Netting vs hedging accounts

MT4 is always hedging: you can hold a buy and a sell on the same pair at the same time, as separate positions. MT5 supports both netting and hedging, and which one you get is decided by the broker or prop firm.

On a netting account you can only have one net position per symbol, so opening an opposing trade reduces or closes the existing one rather than sitting alongside it. This matters enormously for robots. A grid or multi position strategy built assuming hedging will behave completely differently on a netting account, sometimes closing the very positions it was trying to accumulate. Most prop firms offer hedging accounts, but confirm rather than assume, especially before running any strategy that holds several positions on one pair.

Backtesting and optimisation

This is where MT5 is clearly ahead, and it is the reason most robot developers moved. The MT5 strategy tester is multi threaded, so it uses all your processor cores instead of one, which turns an optimisation that took a day into one that takes an hour. It also supports real tick data and multi symbol testing, so you can test a portfolio rather than one pair at a time.

For anyone evaluating a robot, that difference is not cosmetic. It is the gap between a test you can actually run properly and one you shortcut. It is also why you should be sceptical of results with no testing detail attached, as covered in how to spot a fake track record.

The smaller differences

• Timeframes: MT4 has 9, MT5 has 21, including intermediate ones like M2, M10 and H2 that some strategies use.
• Order types: MT5 adds buy stop limit and sell stop limit orders on top of the standard set.
• Asset coverage: MT5 was built for stocks, futures and exchange traded instruments as well as forex, so it handles a broader product range. MT4 is forex and CFD oriented.
• Depth of market: available in MT5, absent in MT4.
• Speed: MT5 is a 64 bit application and generally handles many charts and instruments more comfortably.

So does MT4 still have a case?

A narrowing one. Its real advantage is inventory: two decades of existing indicators, scripts and Expert Advisors written for MQL4, plus a lot of traders who know its interface intimately. If the specific tool you depend on only exists for MT4 and your firm offers MT4, there is no reason to switch for the sake of it.

But for a new prop firm trader in 2026, MT5 is the sensible default. The firms issue it, robot development has moved there, the testing tools are better, and choosing it avoids the compatibility problem entirely.

How to decide in practice

• Check what your firm offers first. This usually settles it, since many now issue MT5 only.
• Match your robot to the platform, not the other way around. Never buy an EA before confirming the platform.
• Confirm netting or hedging if your strategy holds more than one position per symbol.
• Confirm EAs are allowed at all, which varies by firm and is covered in which firms allow trading robots.

The bottom line

MT4 and MT5 are separate platforms with incompatible robot languages, so the practical question is not which is better in the abstract, it is which one your prop firm gives you and whether your automation was built for it. MT5 wins on backtesting, timeframes, order types and asset coverage, and it is now the default across most firms. MT4 keeps a legacy advantage in existing tools. If you are starting fresh and running a robot, use MT5, and verify the netting or hedging setting before you trust any multi position strategy.

An MT4 robot will never run on MT5. Confirm the platform before you buy the automation, not after.

Educational content only, not financial, investment or trading advice. Platform features, account types and prop firm policies vary by broker and firm and change over time. Always confirm which platform your firm issues, whether the account is netting or hedging, and whether Expert Advisors are permitted before trading. Most prop-firm accounts are simulated. No robot guarantees passing a prop firm challenge or any profit. Trading carries substantial risk of loss.