The agreement, which kicks off in January 2022, will see Haeco Americas - the North American airframe MRO unit of Haeco - provide 'extensive interior and exterior modifications'. Works will be carried out at Haeco's Lake City, Florida facility.
Haeco did not state how many aircraft it is slated to work on.
321 Precision Conversions president Gary Warner said: 'The wide-ranging maintenance and conversion experience offered by Haeco is a natural fit for our Airbus A321-200PCF programme as we continue to expand conversion kit capacity to meet high customer demand.'
It was reported in May that 321 Precision Conversions was close to delivering its first Airbus A321 converted freighter, and was due to commence work on a second conversion in June.
Oregon-based Precision Aircraft Solutions formed 321 in partnership with Air Transport Services Group (ATSG), a US air cargo and aircraft services company.