OrigCrossID (FIX tag 551)

StringFIX 4.4

OrigCrossID (tag 551) is a String field defined in FIX 4.4. It appears in 3 message types and is required in 2 of them.

At a glance

Tag: 551
Name: OrigCrossID
Datatype: String
Dialects: FIX 4.4
Messages: 3

What the specification says

CrossID of the previous cross order (NOT the initial cross order of the day) as assigned by the institution, used to identify the previous cross order in Cross Cancel and Cross Cancel/Replace Requests.

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

A real message using tag 551

ExecutionReport · FIX 4.4

Tag	Field	Wire value	Meaning
8	BeginString	FIX.4.4
9	BodyLength	145
35	MsgType	8	Execution Report
49	SenderCompID	BOARTEAM
56	TargetCompID	COUNTERPARTY
34	MsgSeqNum	2
52	SendingTime	20240101-12:00:00.000
37	OrderID	ORD-10042
551	OrigCrossID	EXAMPLE
17	ExecID	EXEC-88117
150	ExecType	0	New
39	OrdStatus	0	New
54	Side	1	Buy
151	LeavesQty	0
14	CumQty	1000000
6	AvgPx	1.09215
10	CheckSum	001

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 551 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	Requiredness	Where in the message
CrossOrderCancelReplaceRequest	t	Required	directly on the message body
CrossOrderCancelRequest	u	Required	directly on the message body
ExecutionReport	8	Optional	directly on the message body

Wire format

Free-form text. Any byte except the SOH separator is legal, so values are not trimmed or case-folded on the wire. @boarteam/fix keeps the value as a string; format rules are checked by validate(), which reports validate/invalid-value rather than throwing.

Read tag 551 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[551];field?.name;   // "OrigCrossID"field?.raw;    // the verbatim wire stringfield?.value;  // coerced to a string

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