After no movement from their bosses at Inland Revenue and the Ministry of Business, public servants will strike again on Monday.
More than 4000 employees walked off the job for two hours on July 9 but, since then, union delegates say "insufficient progress" has been made.
"We very much hoped we would not have to hold this second day of action, but our negotiations with MBIE and IR have made insufficient progress," PSA National Secretary Glenn Barclay said.
He said they were asking for fair pay systems and a modest across-the board pay increase.
"We're not asking the government for a handout, because we believe these two employers can afford it out of their existing baselines."