It’s reasonably well known that New Zealand’s Inland Revenue Department holds millions of dollars of individuals’ unclaimed money. But it’s only a fraction of the money Kiwis have lost track of overseas.

In Australia alone, says Andrew Lendnal, head of marketing at Grosvenor Financial Services Group, up to $3.75 billion of unclaimed superannuation could belong to Kiwis who have moved on. Since 1992, super has been compulsory across the Ditch. Employers are required to contribute 9 per cent of wages to a superannuation account, which can add up to a significant sum of money quickly.

New Zealanders have also lost track of bank accounts, investments, tenancy bonds, life insurance and much more both here and in many of the other countries where they work en masse, such as Britain, the United States, Canada, Ireland and Singapore.

Here in New Zealand, unclaimed money eventually finds its way to the IRD, which lists details on its website at ird.govt.nz/unclaimed-money. The Maori Trustee also has a list of unclaimed money on www.maoritrustee.co.nz.

Nearly one in three people who have at one time been members of an Australian super scheme have lost track of their money and up to a quarter of those could be Kiwis, says Lendnal.

Unlike New Zealand, where you can only have one KiwiSaver account, people who worked in Australia may have built up more than one super fund.

If you move and the super fund can’t track you down, it must eventually move your money to what’s known as an Eligible Rollover Fund, where an estimated A$15 billion ($18.7 billion) is in limbo.

There’s a good reason for Kiwis to start tracking their Australian super funds down, even if they are nowhere near retirement. Next year Kiwis with Australian super will be able to repatriate their money to New Zealand.

That’s not to say they should bring it back. A present it’s financially beneficial to keep that money invested in Australia, where both taxes and fees are more favourable. But many people simply want the money back here for the sake of ease.

“From a tax perspective it may not be good [to repatriate your super], but from the point of view of human nature, clients want their super closer to home. Our advisers say their clients just can’t wait to bring it across.”

When Kiwis left Australia many felt they had lost their super because they didn’t plan to go back to live, says Lendnal.

In anticipation of the passing of the Transtasman Savings Portability legislation, Grosvenor has launched a free “Supertracker” service for Australian superannuation, which can be found at nzkiwisaver.co.nz.

When Grosvenor included details of the service in its annual letter, nearly 10 per cent of clients responded because they had left behind Australian superannuation. Not all of them had lost track of their superannuation, but a proportion had. Others had given it up for dead.

If they prefer, private individuals can use the Australian Tax Office’s Lost Member Register and Superseeker tools, which can be found on ato.gov.au. Other Australian unclaimed money such as dormant bank accounts are listed at fido.gov.au.

Supertracker, says Lendnal, goes a step further than the ATO’s website searches because it helps members track down money that may not yet be handed over to Eligible Rollover Funds and still be held by the original super fund.

He says clients who want to repatriate their money as soon as transtasman portability gets the green light have been consolidating their super funds and parking the money in a superannuation fund run by Grosvenor’s Australian arm in anticipation of bringing it here.

Even if you don’t want to repatriate your super, there is reason to track it down – the fees in the Eligible Rollover Funds are mighty expensive and eat into fund growth. Or it may be that you simply want to consolidate multiple super accounts into one, which will save you money, says Paul Newfield, who leads Mercer’s retirement, risk and finance business in New Zealand.

It hasn’t yet been decided between the New Zealand and Australian Governments if money repatriated from Australian super funds into KiwiSaver will be eligible for mortgage subsidy. If it is, it could give first-home buyers a good reason to bring their Australian superannuation home.

Every country has a different method of keeping safe and paying out unclaimed money.

In most cases, finding out how the system works is as simple as Googling the words “unclaimed money” or “dormant accounts” and the name of the country, which will almost certainly lead to an article such as this outlining what to do in that specific country. Even better, you should be able find the agency that holds the money, such as the Bank of Canada or the Irish National Treasury Management Agency.

Not all countries have a one-stop-shop such as the New Zealand IRD’s unclaimed money service.

In the US, 40 of the 52 states have clubbed together and launched a website – missingmoney.com – which allows you to search for bank accounts and safe deposit box contents, stocks, mutual funds, uncashed cheques, insurance policies, utility deposits and more.

In Britain, a number of different agencies, such as the Pension Service Office, UK Bankers Association and National Savings and Investments, hold separate records. You can pay a “small fixed fee” of £25 ($54) to the Unclaimed Assets Register, uar.co.uk, a private company, to track down your lost money.

Anyone who has worked overseas and hasn’t claimed a tax refund for a part year, when they arrived or left that country, may be due some money. In most countries it’s simple to make a claim, which can usually be done online.

Whatever the circumstances, in order to track down unclaimed money you will need that person’s tax number from the country in question, their death certificate if relevant, and also previous addresses. If you do have these, then it’s possible to reclaim lost money, but not always easy.

Where it starts to become really tricky is tracking down unclaimed money for deceased relatives who have lived overseas.

Sadly, as people age they often forget details of accounts, life insurance, superannuation and other money and even inadvertently destroy paperwork. Or they may never have shared details of their financial lives with beneficiaries of their will.

As a result, it’s not uncommon for a partner to miss out on money he or she is entitled to. That happens in cases where one partner dies and the other isn’t aware that he or she is eligible for a life insurance payout or superannuation. If you don’t know you’re owed something, it’s unlikely you’ll go looking.

That should be a non-issue in New Zealand in future because KiwiSaver details are tied to an individual’s IRD number. The IRD acts as a “universal clearing house” for KiwiSaver, says Newfield.

So far Mercer has been notified by next of kin or estates of the death of a KiwiSaver client. Having said that, the IRD does not directly notify providers of the death of a customer.

If you suspect that you have unclaimed money overseas or a deceased relative did, it’s worth moving quickly.

In some countries the money is protected in perpetuity. In others there may be a time limit.

In Britain, for example, the Government can take money from accounts dormant for more than 15 years. The money is going to be used from next year to fund the Big Society Bank, which will give funds to charity and voluntary groups. There are also time limits elsewhere.