MOST states are now half-way through their grain harvests.

Victoria appears to be the only state which has not yet reached the half-way mark, with bulk handler GrainCorp reporting grain deliveries in the Geelong and Portland zone reaching just less than one million tonnes.

GrainCorp figures for receivals during the past week show the central Queensland harvest is virtually complete and southern Queensland is slowing to a trickle.

The company said harvesting in the Moree/Narrabri area was now 90 per cent complete, while the Liverpool Plains region was just past the half-way mark.

"Central NSW is 75 per cent complete," it said.

"Canola receivals have been strong and space constraints are emerging at some sites."

So far, GrainCorp has received 1.55 million tonnes of grain in Queensland and  3.72 million tonnes in its NSW port regions.

Altogether, 6.26 million tonnes of grain has been delivered to its network.

In South Australia, Viterra has received 2.85 million tonnes of grain, with nearly half of that delivered by growers during the past week.

Viterra said each of its five regions was more than half-way through harvest, with upper Eyre Peninsula growers nearly finished.

Growers in Western Australia delivered more than 1.5 million tonnes of grain during the past week, with wet weather slowing harvesting towards the end of the week.

CBH Group said 4.7 million tonnes had been delivered to its system.

The co-operative was still estimating the state's crop at 8.5-9.3 million tonnes.