Green MP Jan Logie is backing a petition to abolish the requirement for both parents to sign an application for a child's KiwiSaver account, calling on New Zealand to catch up.
Under the current law, a child under the age of 15 requires signatures from two parents when joining the KiwiSaver scheme.
But single mum Jessica Keltie says this law creates unnecessary barriers.
"I provide 100 percent of the care including financial care for my child," she told Newshub. "Why should I have to ask somebody [to sign] who has no interest in helping me or my child?"
Logie told Newshub the current system is a roadblock for solo parents.
"It's time we caught up with the modern world," she told Newshub.
"What is currently in place is a barrier for parents in setting up financial support for their child's future."
She says the law is outdated, paternalistic and doesn't make sense.
"You need the signatures of all parents, regardless of whether there's a protection order in place or how difficult another parent might be to find. That doesn't make sense."
If a second signature can't be provided because a parent has died, the applicant must prove their death in order to open the account with a single signature.
Keltie echoed the sentiment expressing her frustration as a solo parent.
"Life is hard enough for single parents. Why are they making this shit more difficult? It's ridiculous. It's an emotional issue for me and a lot of single parents."
Sam Wheeler-Brown, a financial consultant, has heard of 37 instances in six months of this rule preventing a parent from setting up a KiwiSaver for their child.
"They have every right to give their child a helping hand at starting out in life."
Mike Taylor, chief executive of KiwiSaver provider JUNO, said when a parent doesn't or can't get in contact with their ex-partner, their service does that for them.
"Our members are pretty compliant, and when we contact the second guardian they are happy to accept."
However Taylor did acknowledge on the odd occasion this isn't the case.
"When the guardian/parent finds out they have to get a second guardian they cancel the application because they believe the ex-partner will refuse."
JUNO added their support for the change in law.
"It's in the best interests of the child to open a KiwiSaver account at a young age - the earlier the better."
ANZ also supports the proposed change. A spokesperson told Newshub the bank is eager to see KiwiSaver become more accessible to Kiwis.
Keltie's petition has received more than 1500 signatures and is due to be delivered to Parliament next month.
Minister in charge of KiwiSaver David Clark has been approached by Newshub for comment.