Description

The standard FIX message header

Structure

Tag Field Name Req'd Comments
8 BeginString Y FIXT.1.1 (Always unencrypted, must be first field in message)
9 BodyLength Y (Always unencrypted, must be second field in message)
35 MsgType Y (Always unencrypted, must be third field in message)
1128 ApplVerID N Indicates application version using a service pack identifier. The ApplVerID applies to a specific message occurrence.
1156 ApplExtID N
1129 CstmApplVerID N Used to support bilaterally agreed custom functionality
49 SenderCompID Y (Always unencrypted)
56 TargetCompID Y (Always unencrypted)
115 OnBehalfOfCompID N Trading partner company ID used when sending messages via a third party (Can be embedded within encrypted data section.)
128 DeliverToCompID N Trading partner company ID used when sending messages via a third party (Can be embedded within encrypted data section.)
90 SecureDataLen N Required to identify length of encrypted section of message. (Always unencrypted)
91 SecureData N Required when message body is encrypted. Always immediately follows SecureDataLen field.
34 MsgSeqNum Y (Can be embedded within encrypted data section.)
50 SenderSubID N (Can be embedded within encrypted data section.)
142 SenderLocationID N Sender's LocationID (i.e. geographic location and/or desk) (Can be embedded within encrypted data section.)
57 TargetSubID N "ADMIN" reserved for administrative messages not intended for a specific user. (Can be embedded within encrypted data section.)
143 TargetLocationID N Trading partner LocationID (i.e. geographic location and/or desk) (Can be embedded within encrypted data section.)
116 OnBehalfOfSubID N Trading partner SubID used when delivering messages via a third party. (Can be embedded within encrypted data section.)
144 OnBehalfOfLocationID N Trading partner LocationID (i.e. geographic location and/or desk) used when delivering messages via a third party. (Can be embedded within encrypted data section.)
129 DeliverToSubID N Trading partner SubID used when delivering messages via a third party. (Can be embedded within encrypted data section.)
145 DeliverToLocationID N Trading partner LocationID (i.e. geographic location and/or desk) used when delivering messages via a third party. (Can be embedded within encrypted data section.)
43 PossDupFlag N Always required for retransmitted messages, whether prompted by the sending system or as the result of a resend request. (Can be embedded within encrypted data section.)
97 PossResend N Required when message may be duplicate of another message sent under a different sequence number. (Can be embedded within encrypted data section.)
52 SendingTime Y (Can be embedded within encrypted data section.)
122 OrigSendingTime N Required for message resent as a result of a ResendRequest <2>. If data is not available set to same value as SendingTime (Can be embedded within encrypted data section.)
212 XmlDataLen N Required when specifying XmlData to identify the length of a XmlData message block. (Can be embedded within encrypted data section.)
213 XmlData N

Can contain a XML formatted message block (e.g. FIXML). Always immediately follows XmlDataLen field. (Can be embedded within encrypted data section.)

See Volume 1: FIXML Support

347 MessageEncoding N Type of message encoding (non-ASCII characters) used in a message's "Encoded" fields. Required if any "Encoding" fields are used.
369 LastMsgSeqNumProcessed N The last MsgSeqNum value received by the FIX engine and processed by downstream application, such as trading system or order routing system. Can be specified on every message sent. Useful for detecting a backlog with a counterparty.
Component Block - <HopGrp> N Number of repeating groups of historical "hop" information. Only applicable if OnBehalfOfCompID is used, however, its use is optional. Note that some market regulations or counterparties may require tracking of message hops.

Used In