More than two million Australians are paying up to 46.5 per cent tax on their superannuation contributions and earnings instead of 15 per cent simply because they haven’t provided a tax file number to their fund.

At the end of June 2015, there were almost 2.2 million super fund members, holding $16.3 billion in funds, that were collectively overpaying the Australian Tax Office to the tune of hundreds of millions of dollars a year.

Exactly how much the ATO is creaming in extra tax was not forthcoming from the regulator when asked by The New Daily.

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“Unfortunately, the ATO doesn’t have this data readily available,” a spokesman said.

It pays to do your paper work. Photo: AAP

“We encourage the community to provide their tax file number (TFN) to their employer and/or super fund.

“If you don’t, your super fund may take extra tax out of your super contributions and will not be able to accept any non-employer contributions.”

The Tax Office is raking it in

Based on the 9.8 per cent median return from super funds last financial year, the annual tax windfall to the ATO would have been in excess of $850 million.

Data from the Australian Prudential Regulation Authority shows the average balance across member accounts without a TFN was around $8000.

The superannuation sector is continuing to step up its marketing efforts to address the missing TFN problem.

“We regularly let members know that they could save a lot of money by taking just a few minutes to provide us with their Tax File Number,” HESTA chief executive Debby Blakey told The New Daily.

At the end of last week, HESTA had 8603 members who had not provided a TFN, equating to about one per cent of its members.

“If a super fund doesn’t have someone’s TFN they can end up paying a lot more tax than they need to on their super contributions, and they won’t be able to make after-tax contributions.”

Free cash from the government

Ms Blakey said people can also miss out on the super co-contribution, which is a super bonus of up to $500 from the federal government each year to eligible people who contribute to their super.

“We also often help members find money they didn’t know they had. Members can let us use their TFN to find super they’ve lost track of. The Australian Tax Office at the end of 2015 reported that there was over $16 billion in lost super. We help HESTA members get their super back where it belongs – in their account,” Ms Blakey said.

There could be cash for you. Photo: Getty

Meanwhile, AustralianSuper group executive engagement, advocacy and brand, Georgina Williams, said that out of just over two million members, 97.5 per cent had supplied a valid TFN.

“Simple steps such as supplying your Tax File Number, can boost your retirement savings.”

Provide your TFN and win

“Superannuation is one of the most tax-effective ways of saving for retirement. Providing your TFN will also assist in allowing members to make voluntary payments and consolidate their accounts which will help to further lower their fees.”

A spokesman for Cbus said that as of June 2015, 97.2 per cent of its members (700,500) had provided their TFNs, which was up from 94.9 per cent in 2010.

“Cbus actively encourages members to supply their tax file numbers through a number of mechanisms,” the spokesman said.

“If members haven’t supplied their TFN then this will be highlighted on their annual statement and their record of contributions. In addition, members who haven’t supplied their TFN will get a direct communication each year that highlights the benefits of providing a TFN.”

* The New Daily is owned by a group of industry super funds.