Councillors Helen Craig and Martin Visser argued for a higher rate but were outvoted.
Mrs Craig said a reasonable remuneration was important to attract quality candidates to serve on council and she did not believe the authority "had come to grips" with what was required of councillors.
"A low remuneration level means people will see the job as something they can't undertake," she said.
"It restricts those who will be attracted to serve, and that precludes younger people and business people."
Mr Visser said the suggested figures were "blatantly unfair".
He said a broader range of people needed to be attracted to serve on council and a higher pay rate recognised that.
But Deputy Mayor Hamish McDouall said Whanganui had "one of the most vibrant councils" and it included four members who ran their own businesses and others in fulltime employment.
He acknowledged councillors were underpaid but said increasing the scale was simply "an impost on ratepayers".
"And being a councillor is not a fulltime job. Part of what we do is a pure drive for public service," he said.
THE NUMBERS
These are the pay scales to mayor and councillors after the 2.5 per cent increase:
Mayor - $110,000
Deputy Mayor - $39,848
Councillor with portfolio (8) - $36,260
Councillor without portfolio (3) - $31,878
Rural community board chair - $10,660
Rural community board member - $5330