Instant vs Market Execution: The Setting You Do Not Pick
Two traders place the same order on the same platform at the same moment. One meets a requote box and has to accept a different price. The other is filled straight away, at a price nobody showed them first. Neither trader picked that difference.
The behaviour comes from the execution mode attached to the symbol being traded, and MetaQuotes documentation is explicit that the brokerage company sets it per security. Most explanations of this subject run it as a two-way comparison the reader decides between. It is neither two-way nor a decision.
This page states what each documented mode decides, why a requote belongs to some of them and not others, and what the mode leaves once the order reaches its fill policy.
Key takeaways
- MetaTrader 5 documents four execution modes: Instant, Request, Market and Exchange. MetaTrader 4 documents three. Most comparisons name two.
- The mode belongs to the symbol and the broker sets it. No account setting switches it, and no platform preference overrides it.
- A requote is a defined step of Instant and Request execution. Under Market execution, sending the order is consent to the price, so there is nothing left to requote.
- The mode also limits the fill policy: Instant and Request allow Fill or Kill only, while Market and Exchange allow more.
- Because it is set per symbol, one account can behave one way on a currency pair and another way on an index.
Table of contents
- Your Broker Sets This Per Symbol, and You Do Not Choose It
- The Four Modes MetaTrader Documents, and the One Nobody Lists
- Why a Requote Can Only Happen in Two of Them
- Market Execution Means Consent Before You See the Price
- The Fill Policies Each Mode Leaves You
- Where to Read Your Own Symbol Mode Before You Trade It
- What This Changes for You, and What It Does Not
Your Broker Sets This Per Symbol, and You Do Not Choose It
Both the MetaTrader 4 and the MetaTrader 5 help close their section on execution with the same point: the brokerage decides the mode, and decides it one instrument at a time. That single line settles more than it appears to.
It makes the mode a property of the instrument, not a preference in the account. There is no toggle to find, and no support request that changes it for one trader while leaving it alone for everyone else on the same symbol.
It also means a broker can run one mode on major currency pairs and a different one on indices inside the same login, so an expectation learned on one instrument can fail on another while the platform itself has not changed.
The question worth asking is not which mode to use. It is which mode this symbol is already on, and which fill policy that leaves available.
The Four Modes MetaTrader Documents, and the One Nobody Lists
MetaTrader 5 documentation lists four. Under Instant Execution the platform attaches the current prices to the order and asks the broker to deal at them. Under Request Execution a price is requested from the broker first, arrives, and the trader then confirms or rejects it.
Under Market Execution the broker decides the execution price with no discussion. Under Exchange Execution the operation is sent to an external trading system and meets the prices of current market offers.
MetaTrader 4 documentation lists three of those, naming them Instant Execution, Execution on Request and Execution by Market. Exchange Execution has no MetaTrader 4 entry.
Request Execution is the one that goes missing. Every comparable read for this page ran the subject as Instant against Market and stopped there. A trader on a Request symbol is watching a quote arrive for approval rather than a live stream to hit, and no two-mode explanation accounts for what they are looking at.
Why a Requote Can Only Happen in Two of Them
A requote is often treated as a sign of a particular broker. The documentation treats it as a step in a particular mode.
Under Instant Execution the terminal sends a price along with the order. If the broker will not deal at that price, MetaQuotes describes what comes back precisely: a requote, meaning the broker answers with the prices it will deal at instead. Request Execution has the same shape moved earlier, with the price quoted before the order is sent and the trader given the choice to confirm or reject.
What both share is a moment where two prices exist at once, one held by the trader and one by the broker, and they are allowed to disagree. The requote is what that disagreement looks like on screen, which is also why the platform reports different rejection codes depending on how the order was sent.
Market Execution Means Consent Before You See the Price
What MetaQuotes documents for Market Execution is worth reading slowly. The price is settled by the broker alone, with nothing referred back to the trader, and the act of sending the order is itself approval of whatever that price turns out to be.
Two things follow, and only one of them is usually mentioned. You cannot be requoted, which is the part every comparison highlights. You also cannot refuse, which is the part they leave out. The situation that would have produced a requote elsewhere produces a fill here, at a price approved in advance rather than individually.
That is why the tolerance controls carry the weight under this mode; the mechanics of a fill away from the screen price sit with slippage tolerance rather than with the mode itself.
The Fill Policies Each Mode Leaves You
The mode decides how a price is agreed. It also decides how much of the volume is allowed to trade, because MetaQuotes publishes a compatibility rule between the two. Neither decision touches the order lifetime field, which is set independently of both.
Under Instant and Request Execution, Fill or Kill is the only policy available: the order trades in full or not at all. Market Execution adds Immediate or Cancel and Return. Exchange Execution adds Book or Cancel on top of those. A trader who wants partial fills on a symbol running Instant Execution is not choosing the wrong setting, they are on a symbol where the setting does not exist.
What each of those four policies does with an order is a separate subject, developed on the fill policy page rather than repeated here.
| Execution mode | Who settles the price | Can a requote occur | Fill policies the mode allows |
|---|---|---|---|
| Instant | Trader sends a price, broker accepts or refuses it | Yes | Fill or Kill only |
| Request | Broker quotes first, trader confirms or rejects | Yes | Fill or Kill only |
| Market | Broker, with consent given when the order is sent | No | Fill or Kill, Immediate or Cancel, Return |
| Exchange | The external trading system, at current market offers | No | Fill or Kill, Immediate or Cancel, Return, and Book or Cancel |
Where to Read Your Own Symbol Mode Before You Trade It
Since the setting belongs to the instrument, the answer is found per instrument. MQL5 documentation exposes it as a symbol property, SYMBOL_TRADE_EXEMODE, described as the deal execution mode, and lists the allowed filling modes as a second property beside it.
For a reader not writing code, three checks do the same work. Ask about the symbol rather than the account. Ask again before trading a different asset class with the same broker. And treat a requote as evidence rather than a nuisance: a symbol that can requote you is not running Market Execution, whatever the marketing page says, and that also shapes which order types behave as expected.
What This Changes for You, and What It Does Not
None of this changes what an order asks for. A market order still asks to trade now at the best price available. What the mode changes is where a disagreement about that price is permitted to happen, and whether the trader gets a say when it does. On two of the four modes there is a conversation. On the other two there is a fill, and the conversation happened when the order was sent.
Frequently Asked Questions
What is the difference between market execution and instant execution?
Under instant execution the platform sends a price with the order and the broker can return a requote when that price is not accepted. Under market execution the broker settles the execution price and sending the order counts as consent to it, so no requote step exists at all.
Can I switch my account from instant execution to market execution?
No. MetaQuotes documentation states that the brokerage sets the mode for each security, which makes it a property of the symbol rather than a setting inside the account. The same broker can run different modes on different instruments.
Does a market order always execute immediately?
Not in every case. The mode decides how the price is agreed and the fill policy decides how the volume is treated. Under instant and request execution only fill or kill is available, so an order that cannot be filled in full is not filled at all.
Why does a requote never appear on some symbols?
Because a requote belongs to instant and request execution only. On a symbol set to market or exchange execution there is no point at which the price of the trader and the price of the broker are compared, so nothing can be sent back for approval.
Risk warning: this page is educational and describes how trading platforms document order execution. It is not advice to trade any instrument, to open an account with any broker, or to prefer one execution arrangement over another. Leveraged trading carries a high risk of loss. Execution arrangements are set by each brokerage company and can differ by symbol and change over time, so read the documentation and the contract terms of the broker you trade through before relying on any behaviour described here.