A first-year report card for the Mt Eden private prison has shown it continues to fall well short on several performance measures.
British firm Serco has a $300 million contract with the Government to run the Auckland jail for at least six years.
A report for the year to July shows only 42% of Serco's prisoners had a management plan in place, when 90% or more is the benchmark.
The company only did a six-month review of those prisoner plans in 60% of cases, when 98% was the target.
Just 52% of prisoners were released as per their release plan, when the required level was 98%, and Serco only followed its incident notification process three-quarters of the time.
For its part, Serco says it is returning the lowest positive drug test rates of any prison in New Zealand, as well as maintaining low levels of self-harm and serious assaults.
Results for the month of August show Serco is meeting 34 of its 37 performance targets, and achieving above 90% compliance with its contract.
Corrections Minister Anne Tolley says it is an extremely tough contract, but Serco is making good progress and expects that to continue.