But a rescheduling to March 2022 is being investigated.

The HMFD is the nation's largest field days and outdoor agricultural event, with an economic value of more than $92 million. The event was scheduled for 21-23 September at Henty, New South Wales.

HMFD chief executive officer, Belinda Anderson, said the decision to look into rescheduling was based on the recommendation from NSW Health around the current challenge faced by New South Wales and the possibility of the virus being transmitted into regional areas.

"HMFD has been advised that we are able to operate under the four square metre rule, however, NSW Health has strongly recommended the event be rescheduled," Anderson said.

"We also have considered the possibility of introducing the Delta strain of COVID-19 to the area and the impact this would have on our community. This was a risk we were not prepared to take."

Anderson said border restrictions had also played a significant part in the decision to cancel the September event, with 50 per cent of exhibitors booked from interstate.

"Six weeks from the event seems like a long time but an event of this size does not happen overnight and we owe it to those businesses committed to the 2021 event to give them fair warning," Anderson said.

"The majority of visitors come from within a three-hour drive of Henty signifying there is a great representation from Victoria.

"Snap lock downs will still be possible in September and HMFD cannot risk a repeat of what was seen in Victoria and Queensland on the eve of major agricultural events.

"HMFD management is investigating the option of rescheduling the field days to March 15-17, 2022, and will be contacting exhibitors and key stakeholders regarding this option."

Anderson appealed to exhibitors to be patient as management determines options for refunds or the rollover of fees to the 2022 event.