Susan Edmunds, Money Correspondent
About 200 pensioners have had the amount they receive in NZ Super affected this week because of a problem with the Ministry of Social Development's IT system.
One man who contacted RNZ said he had been receiving NZ Super for more than 10 years, as well as a small proportion from Canada because he had worked there briefly.
But his NZ Super payment did not arrive on Monday.
When he called to ask what had happened, he was told there was a system error and everyone receiving Canadian or Netherlands pensions had their NZ Super suspended.
Paula Ratahi-O'Neill, the ministry's general manger of centralised services, said it was working urgently to fix a fault that affected people receiving overseas pensions.
"The fault was in the IT system that updates overseas pension rates. It has caused a small group of people to have their NZ Super payments incorrectly assessed.
"This has led to some payments being suspended, and in other cases incorrect payments being made.
"We estimate that around 200 clients receiving overseas pensions have been affected. We will continue to monitor numbers.
"We are working with urgency to fix these payments and will be paying amounts owing to people by Friday. We apologise to those impacted by this fault."
She said the ministry's technical team was working "at speed" to stop other payments being affected and a data fix should be released by Monday.
Some overseas pensions that are deemed to be similar to New Zealand's system offset NZ Super.
For every dollar people get from an overseas pension, their New Zealand payment is reduced by one dollar.
According to the government's website, to count as a pension that offsets NZ Super, the pension needs to be part of a programme providing pensions or benefits, cover something that NZ pensions and benefits cover, such as old age or disability, and be administered by or on behalf of a country's government.
Voluntary savings schemes generally were not included.

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