What Is a Trade Copier? MT4 & MT5 Guide

TradeMirror diagram of a source account routing supported MT4 or MT5 events through sizing controls to follower accounts. — A copy route carries supported source events through sizing and protection rules before each follower submits its own broker instruction.

What is a trade copier?

A trade copier is software that watches one trading account—the source—and sends matching trade instructions to one or more follower accounts. When the source opens, changes, or closes a supported position, the copier processes that event for the followers selected in the copy route.

The short answer

A trade copier automates account-to-account trade instructions. It does not choose a strategy, create a signal, or guarantee that every follower receives the same price or result.

With TradeMirror, the accounts must be yours or accounts you are authorized to operate. TradeMirror is not a public trader marketplace and does not select trades on your behalf.

01 · SourceOne connected accountOriginal trade occurs here

02 · Sizing ruleMultiplier or fixed lotOne rule per copy strategy

03 · FollowersSelected follower accountsInstructions are sent to each

Configuration diagram: source account → sizing rule → selected follower accounts. It does not represent an execution receipt.

How does a trade copier work?

A typical account-to-account route follows six steps:

You connect the MT4 or MT5 accounts and test each connection.
You select one account as the source of the original trades.
You choose the follower accounts that should receive eligible instructions.
You configure how follower position size should be calculated.
You review the route and explicitly start the strategy.
The copier processes new source events while the route is running, subject to connection, account, broker, and risk controls.

Saving a route is not the same as starting it. A good copier keeps the selected source, followers, sizing rule, and current state visible so that you can review what is configured before copying begins.

What can be copied?

TradeMirror can process supported position opens, closes, stop-loss changes, and take-profit changes from the source account. Each event becomes an instruction for the selected followers rather than a promise of an identical outcome.

The follower account still submits and executes its own order through its broker. A different spread, available price, liquidity, symbol configuration, margin level, or connection state can change the fill or prevent it entirely.

Source accounts and follower accounts

Source account: The MT4 or MT5 account where the original trade event occurs. A copy strategy has one selected source.
Follower account: An account selected to receive trade instructions from the source through that copy strategy.
Copy strategy: The saved combination of one source, selected followers, a sizing rule, optional risk controls, and a running or stopped state.
Copy route: The configured path from the source through its rules to the followers. It describes the setup, not a guaranteed result.

For a deeper explanation of these roles, read the source and follower account guide.

Can a trade copier work between MT4 and MT5?

Yes. A cross-platform copier can translate supported events between the two account platforms. TradeMirror supports MT4 to MT4, MT5 to MT5, MT4 to MT5, and MT5 to MT4 routes. The source and followers do not all need to use the same MetaTrader version.

Cross-platform support does not make every broker or symbol combination interchangeable. Broker server access, symbol names, contract specifications, minimum lot sizes, and account settings still matter. Test every account connection and route instead of assuming compatibility.

Compare the platform-specific details in the MT4 vs MT5 trade copier guide, then review the extra checks for copying between different brokers.

How is follower lot size calculated?

Position sizing determines the volume requested on a follower. TradeMirror offers two straightforward methods:

Lot multiplier: Scales the source volume. For example, a 0.50 multiplier requests half the source lot size before account and broker constraints are applied.
Fixed lot: Requests the same configured follower volume for every copied open, regardless of the source trade's volume.

Neither method automatically makes risk equal between accounts. Account equity, leverage, symbol contract size, currency, open exposure, and broker rules can differ. Use the lot multiplier vs fixed-lot guide to review worked examples before activation.

Trade copier vs signals, marketplaces, and trading robots

Trade copier: Routes supported trade events from a source account you choose to follower accounts you control.
Signal service: Publishes trade ideas or instructions from a provider. A copier may transport a trade, but it does not create the underlying signal.
Copy-trader marketplace: Lets users discover or follow public traders. TradeMirror is not a marketplace and does not rank or recommend traders.
Trading robot or EA: Uses programmed rules to decide when to trade. A copier transfers source events; it does not decide which trades the source should place.

What are the main trade-copying risks?

Automation reduces manual repetition, not trading risk. Important risks include:

Execution differences: prices, timing, slippage, and fills can differ between source and follower accounts.
Connection failures: a source event or follower instruction can be delayed, rejected, or missed.
Sizing errors: an unsuitable multiplier or fixed lot can create more exposure than intended.
Broker and symbol differences: contract sizes, suffixes, trading hours, minimum volumes, and restrictions can vary.
State assumptions: a saved strategy may be stopped, while a sent instruction does not prove a follower fill.

Read the full risk disclosure and confirm actual positions inside each MetaTrader account. This article is educational and is not investment advice or a recommendation to place any trade.

For a control-by-control setup review, use the trade copier risk-management guide.

How to evaluate a trade copier

Before choosing or activating a copier, check whether it:

Supports the account platforms and route you need.
Tests each connection before the account is used.
Shows the source, followers, sizing rule, and runtime state.
Provides explicit start, stop, and follower controls.
Explains what its dashboard can and cannot prove.
Documents execution, broker, connectivity, and sizing risk.
Lets you test conservatively before relying on a live route.

TradeMirror's pre-flight checklist turns these questions into a repeatable review before activation.

How do I start copying between my accounts?

Begin with two accounts you own or are authorized to operate. Connect and test them, choose the source and follower roles, select a sizing method, review the route, and use a conservative end-to-end test before relying on it.

Follow the step-by-step account-copying guide for the full connection, configuration, testing, and stopping workflow. If an active route does not behave as expected, use the trade copier troubleshooting guide.