The billion-dollar new platform underpinning Australia's payments system has been set live to the public today, but the Commonwealth Bank is the only major bank to open it to customers at launch.

The financial services industry and federal government have been working on the new payments platform (NPP) since early 2012.

The NPP works like a "secure set of rails" between banks so they can send payment messages in real time to each other via the Reserve Bank.

Learn more about the NPP here

The platform allows services to run on top of the NPP - like Bpay’s Osko, which is the first so-called overlay service to arrive on the platform.

Osko lets consumers transfer money to someone via their mobile phone number or email address in real-time, 24/7. It also enables them to send a 280-character description with their payment.

Osko utilises the PayID component of the NPP that lets individuals register an easy-to-remember identifier - like email or phone number - to their bank account.

NPP Australia earlier this month started a campaign to promote PayID and encourage consumers to register for one through their bank.

The NPP went live in November as a pilot for employees at some of the 13 financial institutions participating in the platform.

NPP Australia today said the platform had been made available to the wider public as of 12.01am on Tuesday.

The 13 participating banks will now bring their customers onboard the platform over the coming months.

Around 50 other smaller financial services organisations will also get access to the NPP through the core group.

NPP Australia said the platform's rollout to individual banks would depend on their own "timings and plans".

Banks slow to adopt

But the Commonwealth Bank is the only major bank to fully adopt the platform at launch.

It said customers could now register their mobile number as their PayID through the CommBank app.

ANZ Bank is holding off on rolling the NPP out to its customers while it undertakes "rigorous testing" of the platform.

"We will be announcing how we will roll out real-time payments to all our customers across Australia in the coming weeks," a spokesperson said.

A Westpac spokesperson initially said the NPP would be available to core consumer Westpac customers from today, but later changed this to "in the coming weeks" and for a "small group" of consumer customers.

The NPP will be expanded to other Westpac group businesses - like St George and Bank of Melbourne - "progressively", the spokesperson said.

NAB head of deposits and transaction services Rachel Slade said NAB would roll out NPP features to its customers "within the next month".

The Customer Owned Banking Association (COBA) industry association for credit unions, mutuals and building societies has been contacted for detail on which of its members are offering NPP services.

An NPP Australia spokesperson said "thousands" of payments were already underway on the platform between "a variety of banks, building societies and credit unions".

“The new payments platform has a unique layered 'open access' design which allows for different entities to leverage the platform’s functionality in different way," Lovney said in a statement.

"Innovative organisations can choose to build upon the platform’s capabilities to develop and launch ‘overlay services’ on the platform.

"These could be payments experiences, or they could be business applications that enable significant organisational efficiencies."