Advertising spending by government departments has increased at least 121 percent since Labour was elected, and it cannot be explained solely by the pandemic, National says.
The government argues spending unrelated to Covid-19 is in many cases down compared to five years ago, and department bosses are required justify money being spent.
National's Public Service Spokesperson Simeon Brown compiled data presented to select committees over the past five years, and said it showed departments' and agencies' spending on advertising had increased from $56 million in 2016/17, to more than $124m in 2020/21.
He said New Zealanders would have expected an increase to support vaccination and other Covid-19 messaging, but that did not explain increases from some departments.
"Advertising spending by the Ministry of Justice rose from $350,000 in 2017 to $2.4m in 2021, while the Department of Internal Affairs went from $600,000 in 2017 to $4m in 2021," he said.
"In Labour's first year in office, advertising increased by $20m and then increased even further once Covid-19 arrived."
He said Labour was addicted to spending, and it was time to get that under control.
However, Public Service Minister Chris Hipkins said if Covid-19 was taken out of the equation, advertising spending "in many cases has actually reduced on five years ago".
"The bulk of the increase in advertising spend has been within Health and DPMC, and that's directly connected to the Covid-19 response. The advertising helped New Zealanders understand alert level changes, kept them informed about vaccinations, and promoted public health messages," he said in a statement.
"Public service agencies have a huge job of providing information to the public about services they provide, consultation and engagement with the community, recruitment and other need-to-know info ... IRD's annual tax returns; DOC's efforts to ensure people are looking after our national parks; recruitment campaigns like those in police and education."
He said the numbers tended to move around based on when different departments had specific needs, such as with Stats NZ during the census, and agencies had responsibilities in justifying their budgets.
"There are clear guidelines around advertising and it is for agencies and their chief executives to determine a legitimate purpose. I expect agencies to be informing the public, and I also expect them to be carefully considering their spending."