This year's AgQuip was a beacon of hope for Gunnedah businesses, and news of its cancellation has left many in "shock".
ACM announced the difficult decision on Tuesday and organiser Kate Nugent said they had tried everything to get the highly anticipated agricultural event going amid the COVID-19 crisis.
This means the loss of up to 100,000 visitors and an economic injection of millions of dollars.
Usually held in August, the three-day event had been postponed to November before Monday's official decision by organisers.
Gunnedah Chamber of Commerce and Industry president Juliana McArthur said it had already been "a tough year" for businesses on the back of the drought and COVID lockdown and AgQuip would have been a welcome boost.
"I think it's a blow for local businesses, particularly our hospitality and tourism businesses," Mrs McArthur said.
"It's such a big event for Gunnedah and we really depend on it for business income.
"In some ways [the decision] is not a surprise. We were always hopeful that even though it was moved to November, we could still proceed, but I appreciate organisers have found the decision extremely difficult to make and that they've made that decision in the best interests of all their exhibitors."
It's such a big event for Gunnedah and we really depend on it for business income.Juliana McArthur, Gunnedah Chamber of Commerce and Industry
Gunnedah shire mayor Jamie Chaffey said while the cancellation was "very disappointing news for our community and the economic stimulus that would have been created", he understood that the decision was out of ACM's hands.
"Personally, on behalf of council, I want to commend Kate Nugent and her team for their commitment to do all that they could to attempt to deliver the 48th consecutive AgQuip, understanding it would have been very easy to give up much earlier," Cr Chaffey said.
"We look forward, as I'm sure the rest of the Gunnedah community does, to 2021 when AgQuip will be back bigger, brighter and better for sure, here in Gunnedah."
Ms Nugent said calling quits on this year's event was "not what we wanted" and would be the first time in 38 years that it didn't go ahead.
"We've worked so hard to make it happen, but it's all down to the NSW government," she said.
Ms Nugent said 75 per cent of exhibitors had been booked in and interest had been stronger than last year.
"[It's] disappointing that it will impact on businesses, but the fact is, it is beyond our control," she said.
"It's with great sadness that this has happened, but we're accepting it and moving on looking forward to 2021. That will be a focus for us ... all efforts will be geared to make it different."