The company lost almost their entire annual net profit after tax, declining 95 percent from $564 million to just $30 million compared to last year.

The full-year financial result, issued to the ASX, also shows the company is considering selling part of its proposed Vickery mine.

The Vickery Extension Project is a proposal to construct an open-cut coal mine and associated on-site infrastructure about 25 kilometres north of Gunnedah, in north-eastern NSW.

Whitehaven says it will "explore the potential sell-down and formation of a joint venture" on the project, by selling as much as 30 per cent of its currently 100 per cent share in the mine.

But the company also lists winning Commonwealth approval for expansion of the coal mine as "focus for financial year 2021".

Despite the financial pain, Managing Director and CEO Paul Flynn said he was "proud" of the company's "strong operational performance".

"Significant contraction in coal prices disproportionately impacted our headline financial results but it was pleasing to be able to reward investors and pay out $312m in dividends through the period," he said.

"The NSW Government's recent approval of Vickery was a significant achievement but, given continuing short-term economic uncertainty, we remain cautious about expansion and capital allocation."

The Newcastle Index Price for coal was listed at $73.3 Australian dollars in the latest figures, down from a record high of $187 per ton in 2008.

The coal company is "confident about the continuing demand for high quality coal in a more carbon conscious world" Mr Flynn said.

The $607 million Vickery Extension project was signed off at the state level after winning the approval of the NSW Independent Planning Commission in August.

Whitehaven was ordered to follow 184 conditions to help mitigate against impacts of the mine.