Tourism Holdings is selling its stake in InterCity Holdings to its joint venture partner, just over a year after forming the partnership.
InterCity Group will pay $9.5 million for Tourism Holdings' 49% stake, which represents a loss for THL of $3.7 million.
Tourism Holdings formed the joint venture in November last year in a bid to cut costs.
However, chief executive Grant Webster says the business is not part of its core operations and is better suited to a single committed shareholder.
Mr Webster says Tourism Holdings has also had its licence to operate the Waitomo Glowworm Caves extended by five years to 2027.
The extension also changes the agreement from a licence to a lease and defines the commercial terms.
The new agreement coincides with the start of the rebuild of the caves' visitor centre which was destroyed by fire three years ago.