The number of immigrants who are using language training they paid for as part of their visa requirements has fallen to a new low.
It comes as the number of people buying tuition instead of passing an English language test rose from 336 in 2009 to more than 3140.
The government receives a million dollars a year in revenue from the pre-purchased English as a Foreign Language (ESOL) tuition that has not been used.
Immigration New Zealand said almost a half (45 percent) of immigrants did not use any of the tuition they bought in 2011, which expires at the end of this year.
Statistics from the Tertiary Education Commission (TEC), which administers the scheme, show that in 2005, 1088 used their pre-purchased tuition, and in the same year 1398 people bought it.
But by this year the number who had used their tuition had fallen to 202.
However, immigrants have five years to use the ESOL they have bought.
The scheme enables the partners and adult children of immigrants who obtain residence under the Business, Residence from work, and Skilled Migrant visa categories to pre-purchase English language tuition if they do not have the required level of English.
Much of the increase in people purchasing ESOL since 2012 has come from a law change that extended the system to the parent category.
Before their residence application is approved, new immigrants who pre-pay for English language tuition must sign a contract committing to completing an English language programme within five years of becoming a New Zealand resident.
The Tertiary Education Commission's (TEC) Chief Executive, Tim Fowler, said although the TEC had not commissioned specific research into the parent migrant category, anecdotal information in this area indicated that many new immigrants who enter New Zealand under this category do not attend English language tuition as their focus is on providing family support.
He said: "We recognise that despite committing to participate in English language tuition, not all new migrants are completing these courses.
"The TEC is part of a multi-agency working group which has been researching and developing strategies to ensure new migrants have the information they need to access and enrol in a suitable programme once they arrive in New Zealand.
"Between 2011 and 30 November 2016, 12,035 migrants have invested in English language tuition. Of those 2602 (or 21 percent) have used their payment for English language tuition.
"We want to see this number improve to further enable recent migrants to integrate into New Zealand life and work through taking part in English language programmes. The TEC will focus on this issue as part of the work currently underway."
Immigration New Zealand (INZ) manager Steve McGill said: "In regard to research, INZ is not aware of any research into migrants' experiences in using pre-paid ESOL services.
"However, INZ and TEC have a programme of work underway to increase the uptake of pre-paid ESOL.
"The objective of this is to provide migrants with clearer and more targeted information at every stage of the process - from when they purchase tuition to when they enrol and then when they take courses."