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FIX Adapter Reference Documentation

Sequence Reset (4)


Used to reset the message sequence number or gap fill

Message Direction

From TT FIX Adapter to FIX client and from FIX client to TT FIX Adapter

Message Availability

Use CasePrice SessionOrder Session

Drop Copy


Order Routing


Supported Tags

Tag #Field NameReq’dComments
Component Block <Standard Header>Y35=4 (MsgType)

Indicates that the Sequence Reset message replaces missing administrative or application messages. Valid values include:

  • Y : Gap Fill message, Tag 34 (MsgSeqNum) field is valid
  • N : Sequence Reset, ignore Tag 34 (MsgSeqNum)

Data type: Boolean

Default: N



New sequence number

Data type: SeqNum

Component Block <Standard Trailer>Y

Message Notes

The Sequence Reset (4) message is used to reset the message sequence number when the FIX client and the TT FIX Adapter message sequence numbers do not match. If the message omits Tag 123 (GapFillFlag), the value of Tag 36 (NewSeqNo) indicates the new starting sequence number.

If a FIX client or TT FIX Adapter needs to skip messages that would be included in a resend request, it sets Tag 123 (GapFillFlag) to Y, and the value of Tag 36 (NewSeqNo) represents the sequence number of the next message to be transmitted.

Note: Non-gap fill resets should be used only to when the sequence number differences cannot be resolved.

For more information about sequence resets and gap fills, refer to the FIX 4.2 specification.

Related Information

Logon (A)

Resend Request (2)