MT5 field map

Fields keep MT5's names and meanings, with readable values in place of MT5's numbers: "type": "buy_limit" is ORDER_TYPE_BUY_LIMIT, "type_filling": "ioc" is ORDER_FILLING_IOC.

The trade requestCopy Anchor Link

Every trade call records one MqlTradeRequest and sends it once; every answer shows it as sent, field for field (whether it reached MT5 is the answer's state and result). Fields a call doesn't use carry MT5's empty values: 0, "", fok for type_filling and gtc for type_time.

API field	MT5 field	Meaning
action	action	What the request does.
symbol	symbol	The symbol, exactly as the broker names it.
type	type	The order type.
volume	volume	Lots.
price	price	The price: a pending order's, or the one instant and request execution trade at.
stoplimit	stoplimit	A stop-limit order's limit price, placed once price is reached.
sl	sl	Stop loss price; 0 for none.
tp	tp	Take profit price; 0 for none.
deviation	deviation	The largest difference from price MT5 accepts, in points.
type_filling	type_filling	How the order may fill.
type_time	type_time	How long a pending order lasts.
expiration	expiration	Broker server time, seconds since 1970, as MT5 takes it.
order	order	The pending order the request is about (modify, remove).
position	position	The position the request is about (close, stops, close by).
position_by	position_by	The opposite position, for close by.
magic	magic	Your own number, kept by MT5 on the order, its deals and its position.
comment	comment	Up to 31 characters, kept by MT5 on the order.

What each call fills in, beyond the fields you send:

Nothing else is set for you: no price for a market order, no filling mode, no rounding. A dry run sends the same request to MT5's OrderCheck without trading.

Bodies you sendCopy Anchor Link

Place an order and Check an order:

API field	MT5 field	Meaning
symbol	symbol	The symbol exactly as the broker names it, such as EURUSD.
type	type	What to send.
volume	volume	Lots.
type_filling	type_filling	How the order may fill.
price	price	Required for pending orders: the price the order waits for.
stoplimit	stoplimit	Required for buy_stop_limit and sell_stop_limit: the price of the limit order placed once price is reached.
sl	sl	Stop loss price, set in the same request.
tp	tp	Take profit price, set in the same request.
deviation	deviation	The largest difference from price MT5 accepts, in points, for instant or request execution.
type_time	type_time	How long a pending order lasts.
expiration	expiration	When a pending order expires: broker server time, seconds since 1970.
magic	magic	Your own number for the order, kept by MT5 on the order, its deals and its position.
comment	comment	Up to 31 characters, kept by MT5 on the order.

Modify an order:

API field	MT5 field	Meaning
price	price	The price the order waits for.
sl	sl	Stop loss price; 0 removes it.
tp	tp	Take profit price; 0 removes it.
type_time	type_time	How long the order lasts.
stoplimit	stoplimit	Required when the order is a stop-limit order: the price of the limit order placed once price is reached.
expiration	expiration	When the order expires: broker server time, seconds since 1970.

Close a position:

API field	MT5 field	Meaning
volume	volume	Lots to close: the position's whole volume, or part of it.
type_filling	type_filling	How the closing deal may fill.
price	price	Sent as given (0 if left out): brokers with instant or request execution need it, those with market or exchange execution ignore it.
deviation	deviation	The largest difference from price MT5 accepts, in points, for instant or request execution.
magic	magic	Your own number, kept by MT5 on the closing deal.
comment	comment	Up to 31 characters, kept by MT5 on the closing deal.

Set stops (PositionLevels) and Close by (CloseBy):

API field	MT5 field	Meaning
sl	sl	Stop loss price; 0 removes it.
tp	tp	Take profit price; 0 removes it.

API field	MT5 field	Meaning
position_by	position_by	The opposite position's ticket.

MT5's answerCopy Anchor Link

A trade's result is MT5's MqlTradeResult:

API field	MT5 field	Meaning
retcode	retcode	MT5's return code: see Errors and retcodes.
retcode_name	Pipsocket	The return code's name; UNKNOWN for a code MT5 doesn't document.
comment	comment	The broker's comment on the answer.
order	order	The order's ticket, if one was placed.
deal	deal	The deal's ticket, if one was made.
position	Pipsocket	The position's ticket, where the trade server gives it.
volume	volume	The volume dealt.
price	price	The price dealt.
bid	bid	The bid when the request was handled (requotes).
ask	ask	The ask when the request was handled (requotes).
retcode_external	retcode_external	The external trading system's code, if the broker routes to one.

A dry run's result is MT5's MqlTradeCheckResult:

API field	MT5 field	Meaning
passed	Pipsocket	Whether OrderCheck passed the request.
retcode	retcode	MT5's return code: 0 when the check passed.
retcode_name	Pipsocket	The return code's name; UNKNOWN for a code MT5 doesn't document.
comment	comment
balance	balance	The balance after the trade.
equity	equity	The equity after the trade.
profit	profit	The floating profit after the trade.
margin	margin	The margin the trade takes.
margin_free	margin_free	The free margin after the trade.
margin_level	margin_level	The margin level after the trade, in percent.

The account's stateCopy Anchor Link

Positions (POSITION_*):

API field	MT5 field	Meaning
ticket	POSITION_TICKET	The position's ticket: use it to close the position or set its stops.
identifier	POSITION_IDENTIFIER	The position's id, which stays the same if the broker changes the ticket.
symbol	POSITION_SYMBOL
type	Pipsocket	buy or sell (MT5's POSITION_TYPE).
volume	POSITION_VOLUME
price_open	POSITION_PRICE_OPEN
sl	POSITION_SL
tp	POSITION_TP
magic	POSITION_MAGIC
comment	POSITION_COMMENT
time_msc	POSITION_TIME_MSC	When it was opened: broker server time, milliseconds since 1970.

Pending orders (ORDER_*):

API field	MT5 field	Meaning
ticket	ORDER_TICKET
symbol	ORDER_SYMBOL
type	ORDER_TYPE	MT5's ENUM_ORDER_TYPE: buy and sell are market orders (ORDER_TYPE_BUY, ORDER_TYPE_SELL); buy_limit, sell_limit, buy_stop, sell_stop, buy_stop_limit and sell_stop_limit are pending orders (ORDER_TYPE_BUY_LIMIT and so on); close_by is ORDER_TYPE_CLOSE_BY.
volume_initial	ORDER_VOLUME_INITIAL
volume_current	ORDER_VOLUME_CURRENT
price_open	ORDER_PRICE_OPEN
sl	ORDER_SL
tp	ORDER_TP
magic	ORDER_MAGIC
comment	ORDER_COMMENT
position	ORDER_POSITION_ID	The position the order belongs to, if any.

Deals (DEAL_*), in history and on the stream:

API field	MT5 field	Meaning
ticket	DEAL_TICKET
order	DEAL_ORDER	The order that made the deal.
position	DEAL_POSITION_ID	The position's id (identifier).
symbol	DEAL_SYMBOL
type	Pipsocket	MT5's DEAL_TYPE: buy, sell, or a balance operation.
entry	Pipsocket	MT5's DEAL_ENTRY: in opens or adds, out closes, inout reverses, out_by closes by an opposite position.
reason	Pipsocket	MT5's DEAL_REASON: who or what made the deal (expert for the API, sl, tp, so for a stop out).
volume	DEAL_VOLUME
price	DEAL_PRICE
profit	DEAL_PROFIT
commission	DEAL_COMMISSION
swap	DEAL_SWAP
fee	DEAL_FEE
magic	DEAL_MAGIC
comment	DEAL_COMMENT
time_msc	DEAL_TIME_MSC	Broker server time, milliseconds since 1970.

Past orders:

API field	MT5 field	Meaning
ticket	ORDER_TICKET
symbol	ORDER_SYMBOL
type	ORDER_TYPE	MT5's ENUM_ORDER_TYPE: buy and sell are market orders (ORDER_TYPE_BUY, ORDER_TYPE_SELL); buy_limit, sell_limit, buy_stop, sell_stop, buy_stop_limit and sell_stop_limit are pending orders (ORDER_TYPE_BUY_LIMIT and so on); close_by is ORDER_TYPE_CLOSE_BY.
state	Pipsocket	MT5's ORDER_STATE.
volume_initial	ORDER_VOLUME_INITIAL
volume_current	ORDER_VOLUME_CURRENT
price_open	ORDER_PRICE_OPEN
magic	ORDER_MAGIC
comment	ORDER_COMMENT
position	ORDER_POSITION_ID
time_setup_msc	ORDER_TIME_SETUP_MSC	Broker server time, milliseconds since 1970.
time_done_msc	ORDER_TIME_DONE_MSC	Broker server time, milliseconds since 1970.

A symbol (SYMBOL_*):

API field	MT5 field	Meaning
name	SYMBOL_NAME
available	Pipsocket	Whether the terminal could read its properties; when false the rest are empty values.
description	SYMBOL_DESCRIPTION
digits	SYMBOL_DIGITS
point	SYMBOL_POINT
tick_size	SYMBOL_TRADE_TICK_SIZE
tick_value	SYMBOL_TRADE_TICK_VALUE
contract_size	SYMBOL_TRADE_CONTRACT_SIZE
volume_min	SYMBOL_VOLUME_MIN
volume_max	SYMBOL_VOLUME_MAX
volume_step	SYMBOL_VOLUME_STEP
stops_level	SYMBOL_TRADE_STOPS_LEVEL	The closest stops may be to the price, in points.
freeze_level	SYMBOL_TRADE_FREEZE_LEVEL	How close to the price an order or stop is frozen, in points.
filling_mode	SYMBOL_FILLING_MODE	MT5's flags, as filling_modes spells them out.
trade_mode	SYMBOL_TRADE_MODE	MT5's value, as trading spells it out.
execution_mode	SYMBOL_TRADE_EXEMODE	MT5's value, as execution spells it out.
order_mode	SYMBOL_ORDER_MODE	MT5's flags, as order_types spells them out.
expiration_mode	SYMBOL_EXPIRATION_MODE	MT5's flags, as expirations spells them out.
currency_base	SYMBOL_CURRENCY_BASE
currency_profit	SYMBOL_CURRENCY_PROFIT
currency_margin	SYMBOL_CURRENCY_MARGIN
filling_modes	Pipsocket	The type_filling modes MT5's SYMBOL_FILLING_MODE flags allow.
execution	Pipsocket	MT5's SYMBOL_TRADE_EXEMODE.
order_types	Pipsocket	The orders the symbol allows (MT5's SYMBOL_ORDER_MODE).
expirations	Pipsocket	The type_time values the symbol allows (MT5's SYMBOL_EXPIRATION_MODE).
trading	Pipsocket	MT5's SYMBOL_TRADE_MODE: whether and which way the symbol can be traded.

A tick (MqlTick):

API field	MT5 field	Meaning
symbol	Pipsocket
bid	bid
ask	ask
time_msc	time_msc	Broker server time, milliseconds since 1970.
last	last
volume	volume_real
flags	flags	MT5's TICK_FLAG_* bits: what changed.