The company is still assessing the impact of the underground incident that killed one contractor and injured two employees.
Rainy River's outlook is in line with the annualised performance over the past two quarters, when the mill ran at 27,000t/day. New Gold expects full-year cash costs to come in at US$715-795/oz Au-eq, and believes Rainy River can generate "ample free cash at high margins this year".
CEO Renaud Adams said New Gold continued to focus on operational and cost optimisation at Rainy River.
"We will also evaluate the potential expansion of the underground mine beyond the current life of mine, focusing on organic growth opportunities and advancing the exploration programme," he said.
While investigations into the mudslide continues at New Afton, some underground activity has restarted with the mine currently said to be operating at 3,000-5,000 t/d.
The mill is processing material from underground and stockpiles.