As per FIX Standard what will be the maximum length of any Field Name?


Does FIX standard specify the maximum length for Field Names?
Right now I am using String for Field Names but if there is any specific Max Length for Field Names then I can use the same.

Thanks & Regards,


Are you asking about the length of the names themselves or their content? There is no limitation for the name and there are quite long ones in the area of OTC derivatives. The objective is to have proper names revealing key elements of the field’s semantics. At the same time, the shorter the better. For FIXML, the name is then abbreviated based on standard abbreviations for the different terms of the name.


Thanks a lot.
I was asking for the Length of Field Names itself.
Will code accordingly for the FIX builder and parser.


Here some examples of really long FIX field names:

  • UnderlyingStreamEffectiveDateBusinessDayConvention(40058)
  • ProvisionOptionRelevantUnderlyingDateBusinessDayConvention(40156)
  • LegPaymentStreamNonDeliverableFixingDatesBusinessDayConvention(40360)


In FIX Repository, type FieldName_t was defined with a maximum length of 255. Due to an apparent error, the type was not enforced. However, that error has corrected in Orchestra, the successor to FIX Repository. Therefore, in the future the maximum length will be enforced, although I doubt that length should cause problems for anyone.