Fund managers expect Meridian Energy will likely list on the New Zealand stock exchange on either Friday 18 October or a week later.
Meridian will report its annual results on Monday and analysts are expecting a significant increase in operating earnings from the $477 million it reported for the 12 months ended June 2012.
Tyndall Investment Management head of equities Rickey Ward is expecting a reflection of a very challenging period, which includes last summer's drought.
He said signs indicate the fourth quarter was a pretty good period for the company which may mean very close to normalised earnings for the full year.
Mr Ward said he is not expecting too much in the way of forward looking statements as he expects those details to be released closer to the time the company is put up for partial sale.
He said most people are picking a listing date in mid to late October.
Devon Funds Management analyst Phil Anderson said he has heard the same likely dates for the float.
He is expecting Meridian's annual operating earnings will be about $550 million.
Mr Anderson said Meridian lost quite a few customers at the start of the year and has recently ramped up its marketing efforts to try to slowly increase its market share again.