The results show how legal and running costs jumped as the inquiry went on.
The Post Office spent £82m in the 12 months to 31 March, £38m the previous 12 months, and £12m in the year prior to that.
The results also show to what extent legal costs and redress are weighing on its finances.
It showed that pre-tax losses widened to £612m -up from £81m the previous year – while its debts have soared to more than the value of everything it owns.
The release of the numbers comes after two-and-a-half years of evidence hearing sessions drew to a close this week and final statements were submitted.
Commenting on the milestone, Mr Railton said “there remains much to learn and to embed into our organisation culturally as we move forward.”
Its chief executive also said on Thursday that the organisation expects the figure paid out in compensation to increase in the new year as it continues “to quicken the pace on payments”.
He added, however, that ”no amount of financial redress can replace what has been lost to victims”.
Nick Read will also not receive a bonus, having waived his rights to it when he resigned in September after months of scrutiny for the organisation.
