Compare FIX Versions
What changes when a session moves from one FIX version to another: messages and fields added and removed, new and dropped values in the fields that drive order handling, and the points that break real integrations.
| Comparison | Messages added | Fields added | Fields removed |
|---|---|---|---|
| FIX 4.2 vs FIX 4.4 | 47 | 542 | 35 |
| FIX 4.4 vs FIX 5.0 SP2 | 71 | 5,116 | 0 |
| FIX 4.0 vs FIX 4.2 | 19 | 267 | 0 |
| FIX 4.3 vs FIX 4.4 | 25 | 298 | 21 |
| FIX 5.0 vs FIX 5.0 SP2 | 63 | 4,928 | 0 |
| FIX 4.2 vs FIX 5.0 SP2 | 118 | 5,658 | 35 |
- FIX 4.2 vs FIX 4.4
What changed from FIX 4.2 to FIX 4.4: new messages and tags, removed fields such as ExecTransType (20), new ExecType and OrdStatus values, migration tips.
- FIX 4.4 vs FIX 5.0 SP2
What changes from FIX 4.4 to FIX 5.0 SP2: the FIXT.1.1 session layer, ApplVerID, new messages and tags, new enum values and relaxed required fields.
- FIX 4.0 vs FIX 4.2
What changed from FIX 4.0 to FIX 4.2: ExecType and LeavesQty, market data and security messages, Business Message Reject and session reject reasons.
- FIX 4.3 vs FIX 4.4
What changed from FIX 4.3 to FIX 4.4: removed ExecType and OrdStatus codes, renamed settlement fields, new trade capture, position and collateral messages.
- FIX 5.0 vs FIX 5.0 SP2
What FIX 5.0 SP1 and SP2 add to FIX 5.0: market structure and mass action messages, extension pack fields, new enum values and renamed fields.
- FIX 4.2 vs FIX 5.0 SP2
Moving from FIX 4.2 to FIX 5.0 SP2: FIXT.1.1 and ApplVerID, execution reporting changes, removed and renamed fields, and the new messages and tags.
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