The Reserve Bank of Australia (RBA) sees no sense in putting tactile markings on bank notes.
It has made Oakhurst mum Ally Lancaster determined to continue the fight on behalf of son Connor McLeod and others who are vision impaired.
She and Connor, 12, will meet Parliamentary Secretary to the Treasurer Steven Ciobo in Canberra on Thursday in the hope the federal government will intervene.
As the Star reported in January, the only way Connor can tell the difference between the cash denominations is through coins.
Chifley MP Ed Husic recently mentioned the Star's story in federal parliament. Ms Lancaster set up a petition on change.org three months ago, with signatures in support now standing at 53,500, but none of that was enough for the RBA.
"They're not committed to any more accessibility features on bank notes," she said. "They want to continue what they have doing since the 1980s."
The RBA has said that a cash test card using the length differentials is free to those in need.
"But I challenge anyone to identify which one it is while blindfolded," Ms Lancaster said.
Ms Lancaster has sought legal advice and won't rule out more action.
"Connor needs this and it's my job to support him. I won't stop until bank notes are made accessible for everyone with an impairment, not just my son," she said.