Spread (FIX tag 218)

PriceOffsetFIX 4.4FIX 4.2

Spread (tag 218) is a PriceOffset field defined in FIX 4.4 and FIX 4.2. It appears in 22 message types, always optionally. FIX 4.2 calls this field SpreadToBenchmark; the tag number is unchanged, so the two are the same field on the wire.

Also known as SpreadToBenchmark

FIX 4.2 calls tag 218 SpreadToBenchmark. It is the same field on the wire — only the name changed — so a message encoded by either side interoperates.

At a glance

Tag: 218
Name: Spread
Datatype: PriceOffset (float)
Dialects: FIX 4.4 and FIX 4.2
Messages: 22

What the specification says

FIX 4.4

For Fixed Income. Either Swap Spread or Spread to Benchmark depending upon the order type. Spread to Benchmark: Basis points relative to a benchmark. To be expressed as "count of basis points" (vs. an absolute value). E.g. High Grade Corporate Bonds may express price as basis points relative to benchmark (the BenchmarkCurveName(221) field). Note: Basis points can be negative. Swap Spread: Target spread for a swap.

FIX 4.2

For Fixed Income. Basis points relative to a benchmark. To be expressed as "count of basis points" (vs. an absolute value). E.g. High Grade Corporate Bonds may express price as basis points relative to benchmark (the Benchmark field). Note: Basis points can be negative.

Descriptions are quoted from the FIX Orchestra sources under the Apache 2.0 licence.

A real message using tag 218

NewOrderSingle · FIX 4.4

Tag	Field	Wire value	Meaning
8	BeginString	FIX.4.4
9	BodyLength	123
35	MsgType	D	Order – Single
49	SenderCompID	BOARTEAM
56	TargetCompID	COUNTERPARTY
34	MsgSeqNum	2
52	SendingTime	20240101-12:00:00.000
11	ClOrdID	ORD-10042
54	Side	1	Buy
60	TransactTime	20240101-12:00:00.000
40	OrdType	1	Market
218	Spread	0.00010
10	CheckSum	027

Edit and decode it yourself

Shown with | separators for readability. On the wire FIX uses SOH (0x01), an invisible control byte — and because BodyLength and CheckSum are computed over the actual bytes, the two forms have different checksums. Both are valid and both decode here.

Open in the full decoder →

Generated from the FIX 4.4 dictionary and verified at build time: it parses and validates with no issues. Open the decoder to try your own message.

Where tag 218 appears

Requiredness is a property of the message, not of the field: the same tag can be optional in one message and conditionally required in another.

Message	MsgType	FIX 4.4	FIX 4.2	Where in the message
AllocationInstruction	J	Optional	—	inside the SpreadOrBenchmarkCurveData component
AllocationReport	AS	Optional	—	inside the SpreadOrBenchmarkCurveData component
CollateralAssignment	AY	Optional	—	inside the SpreadOrBenchmarkCurveData component
CollateralInquiry	BB	Optional	—	inside the SpreadOrBenchmarkCurveData component
CollateralReport	BA	Optional	—	inside the SpreadOrBenchmarkCurveData component
CollateralRequest	AX	Optional	—	inside the SpreadOrBenchmarkCurveData component
CollateralResponse	AZ	Optional	—	inside the SpreadOrBenchmarkCurveData component
Confirmation	AK	Optional	—	inside the SpreadOrBenchmarkCurveData component
CrossOrderCancelReplaceRequest	t	Optional	—	inside the SpreadOrBenchmarkCurveData component
ExecutionReport	8	Optional	—	inside the SpreadOrBenchmarkCurveData component
IOI	6	Optional	Optional	inside the SpreadOrBenchmarkCurveData component
NewOrderCross	s	Optional	—	inside the SpreadOrBenchmarkCurveData component
NewOrderList	E	Optional	—	inside ListOrdGrp › SpreadOrBenchmarkCurveData
NewOrderSingle	D	Optional	—	inside the SpreadOrBenchmarkCurveData component
OrderCancelReplaceRequest	G	Optional	—	inside the SpreadOrBenchmarkCurveData component
Quote	S	Optional	—	inside the SpreadOrBenchmarkCurveData component
QuoteRequest	R	Optional	—	inside QuotReqGrp › SpreadOrBenchmarkCurveData
QuoteRequestReject	AG	Optional	—	inside QuotReqRjctGrp › SpreadOrBenchmarkCurveData
QuoteResponse	AJ	Optional	—	inside the SpreadOrBenchmarkCurveData component
QuoteStatusReport	AI	Optional	—	inside the SpreadOrBenchmarkCurveData component
SecurityList	y	Optional	—	inside SecListGrp › SpreadOrBenchmarkCurveData
TradeCaptureReport	AE	Optional	—	inside the SpreadOrBenchmarkCurveData component

Wire format

A signed decimal price delta. Negative values are legal and meaningful. @boarteam/fix parses the value as a number and reports parse/invalid-float when it does not lex as one; the raw string is kept so precision and trailing zeros are never lost.

Read tag 218 in TypeScript

decode.tsts

import { createFixEngine } from "@boarteam/fix";import { dictionary } from "@boarteam/fix-dict-fix44";const fix = createFixEngine(dictionary);const { message, issues } = fix.parse(raw);const field = message.fields[218];field?.name;   // "Spread"field?.raw;    // the verbatim wire stringfield?.value;  // coerced to a number

Other PriceOffset fields

Decode this in your own code

The same engine that produced the decoded example above is an Apache-2.0 npm package with zero runtime dependencies. It runs in Node and in the browser, and parse() returns problems as data instead of throwing.

npm i @boarteam/fix @boarteam/fix-dict-fix44

Try the decoder Source on GitHub