Auckland Future candidates must be loyal to the ticket, its elected officials and leader, and abide by any decisions and policy set by the executive committee.
Auckland Future spokeswoman and councillor Denise Krum said voters deserve to know that the candidates they vote for will apply fiscal discipline to their decision making.
"They are crying out for certainty in decision making round the council table," she said.
Mr Cashmore, Mr Penrose and Ms Cooper have consistently voted for the policy platform of Mr Brown, including a 9.9 per cent rates rise this financial year.
Mr Cashmore and Ms Cooper said they planned to have discussions with Auckland Future about its fiscal policy.
Mr Cashmore said he could potentially sign up once he had seen the books and data behind the policies, which include a 2 per cent cap on household rates for three years and cutting $500 million of waste over the remainder of the 10-year budget.
"I'm not going to pledge to something that has no depth to it. My vote is going to someone who has substance beneath the rhetoric," he said.
Mr Cashmore was unapologetic for supporting policies to meet the challenge of growth.
"Auckland deserves collaborative decision making," said Mr Cashmore, who came up with the ballpark figure of $114 for a transport-targeted rate that pushed household rates to 9.9 per cent.
Ms Cooper also wants to see Auckland Future's numbers before considering signing the pledge.
Mr Penrose said if he decides to stand again for council he will stand as an independent. He did not believe signing up to a fiscal envelope.
"For people to go out and say we are going to hold the rates to 2 per cent, well good luck to them," he said.
Mr Penrose said the city was just about gridlocked and facing a transport crisis.
"I don't sit on the fence and throw stones. I try to find the best way forward to work with
Government to get some serious capital into Auckland.
"I'm reluctantly saying no to stuff but, hey, at the end of the day we have got to build this city. Auckland is going off like a firecraker," he said.
Mr Penrose said he tried to be as fiscal as possible, adding he did not sign away $15 million on the St James Theatre or support $3 million for an organ in Parnell which so-called "fiscal" councillors backed.
Auckland Future campaign spokeswoman Sue Wood said the ticket was in discussion with the three councillors, but hoped they would sign the pledge.
She acknowledged their sentiment that it was a very challenging task for those elected to govern the city.
"It is for this very reason that Auckland Future was formed - to achieve a centre-right majority of elected councillors who sign up to a fiscally responsible pledge that provides voters with certainty on rating targets and how to achieve these over the next three years.
"Auckland Future is working with sitting councillors, independents and its own newly selected candidates to achieve a cohesive and disciplined centre-right majority for Aucklanders. The status quo is not the solution," Ms Wood said.
