The June estimate of NOK 49.3 billion to NOK 51.3 billion, excluding ships, had indicated that regular deliveries of liquefied natural gas from the development could be up to 12 months late.
According to the review, the Snøhvit partners should be able to start delivering part of the planned gas volume as early as the autumn of 2006.
Regular gas deliveries are expected to begin in the first quarter of 2007 - six months behind the original timetable.
Statoil's board is to discuss the case shortly.
The group has a 33.53 per cent interest in the field, with Petoro (30 per cent), Total (18.4), Gaz de France (12), Amerada Hess (3.26) and RWE Dea (2.81) as its partners.