Aurizon Holdings (ASX:AZJ) priced an offering of AU$500 million of subordinated notes due 2055, according to a May 9 filing with the Australian bourse.

The notes, issued in two AU$250 million tranches, one floating rate and one fixed-to-floating, will not be listed and are expected to receive 50% equity credit from both Moody's and S&P, the filing said.

The securities are callable from Aug. 16, 2030, and mature on May 16, 2055, unless redeemed earlier, the filing added.

The floating tranche will pay interest at the three-month bank bill swap rate plus 280 basis points, while the fixed tranche will pay 6.3% per annum until the first call date, after which it resets to floating, Aurizon said.

Proceeds will be used to refinance debt and for general corporate purposes, the company added.