Vector has won a High Court fight with Inland Revenue and says is now entitled to a $7.6 million tax refund.
Vector earlier this month appeared before Justice John Faire arguing with IRD about whether $53 million the electricity company received from Transpower is taxable.
The IRD's position was the payments are taxable, Vector's position was that they are not.
Vector, which already paid the disputed tax amount, was pursuing court proceedings to have the IRD reimburse the money.
In a decision released this afternoon, Justice Faire sided with lines company.
"The judgment has found in favour of Vector that a payment of around $53 million relating to access rights to Vector's CBD tunnel was not taxable", the company said in a statement