The Northern Territory will miss its target to have 80 per cent of its eligible population fully vaccinated against COVID-19 by early November.
Chief Minister Michael Gunner released the aspirational plan in mid-September, saying "we are now in a 50-day race to freedom".
But 27 days into that race, the territory's vaccine rollout is dawdling.
A government spokesman told AAP the target rate is unlikely to be reached until several weeks after the planned date.
It was now likely to be late in the month, he said.
According to the NT government, 66 per cent of the eligible population was fully vaccinated as of Monday.
That's up from the 52 per cent of Territorians over 16 who were fully vaccinated on September 15, but still a long way from the 80 per cent mark.
The task becomes even tougher if the commonwealth's vaccination figures for the NT are used.
It says 56.4 per cent of Territorians are vaccinated as of Saturday, according to Medicare card data.
The NT's sluggish vaccination rate comes amid a "six-week vaccination blitz" that is almost complete.
The "freedom" plan also requires most remote Indigenous communities to hit the 80 per cent fully vaccinated rate, with a small number of stragglers likely to face travel restrictions to protect their vulnerable residents.
But the vaccination rate for remote areas is lagging even further behind the overall NT rate, with 44 per cent of residents fully vaccinated.
That's just one per cent higher than it was when the NT started its vaccination rate on September 15.
Health Minister Natasha Fyles said she was extremely concerned about the low rate.
"Some communities, where it might be just a couple of hundred people, we have virtually no protection with the vaccine," she said.
"We have visited those communities multiple times, we have provided information in language (and) we are working with community leaders."
Vaccine hesitancy linked to misinformation about its safety has been blamed for the slow uptake.
NT government data shows about one-fifth of reporting communities have 10 per cent or less of the population fully vaccinated.
Ms Fyles said it was likely some remote communities won't reach the required 80 per cent double vaccinated rate with the rest of the NT.
She declined to say whether the NT would fully open up if remote vaccination remained behind the territory's overall rate once it hit the 80 per cent mark.
The NT's 80 per cent fully vaccinated target is the trigger for stage three of the national plan for the NT.
It includes mandatory vaccinations for workers in high-risk settings, along with new border, quarantine and lockdown rules.
Australian Associated Press