NSW Rural Fire Service members have spent the last five days working to control a fire in Oxley Wild Rivers National Park, near Walcha.
The blaze has burnt about 3400 hectares of bushland in remote, rugged country.
The RFS expects to contain the fire in the next couple of days, incident controller Superintendent Chris Wallbridge said.
One isolated hut was burnt; otherwise, no other property has been damaged.
No people have been harmed.
Easterly winds may bring smoke to Uralla, Armidale, Guyra, and surrounding areas.
Otherwise, there is low risk over the next three days of the fire spreading, fire crews said.
The cause of the fire is still under investigation.
The fire was reported on Saturday, in an area of Melrose Road, north-east of Walcha.
Fire crews and heavy plant worked all night to contain the fire, ahead of what was severe fire weather predicted for Sunday.
Sunday saw a total fire ban across the region, and a severe fire danger warning issued.
The afternoon's temperature of more than 31 degrees, and strong, gusty winds of up to 80km an hour made the fire spot out of containment, and run to the east very quickly.
Fire crews worked with helicopters and large air tankers to control the fire, using natural containment lines (Macleay River, Postman's Creek, Blue Mountain Creek), fire trails, and property boundary fencelines.
The RFS is urging locals to be prepared.
“We’re encouraging everybody to consider your bushfire survival plan in the first instance, and your property management plans for larger properties,” Supt Wallbridge said.