Kiwis around the country have been issued more than $83m of tax refunds by Inland Revenue in their first week of automatic tax assessments.
More than 178,000 people were issued refunds, while just under 40,000 were told they had already paid the correct amount of tax.
Unfortunately for more than 29,000 Kiwis, they were issued emails warning they owed money to the IRD.
While $83m was paid out, there was more than $10.4m of bills to pay back.
The Inland Revenue started sending the first batch of more than 2.5 million automated tax statements last week.
Deputy Commissioner, Transformation, Greg James says the sort of numbers the new system is dealing with is far exceeding expectations.
"Almost every day we're seeing myIR break new records with the number of customers logging in. Yesterday alone, we had just under 500,000 logins from customers completing a wide range of tasks.
"That would have been enough to either see the old system grind to a halt or slow down considerably," he said, "but the new system takes this in its stride.
"Of course, our latest release hasn't been without its wrinkles and that's to be expected with a transformation of this size and scale.
"Tax agents in particular are playing a valuable role in letting us know when something isn't happening as they would expect. We're grateful for that contribution and we're trying to be as responsive as possible in making any enhancements or adjustments.
"We're really encouraged to see so many customers are able to get on with their business.
"Some aspects will still take some getting used to and there are definitely some features that could be better but what we have now is far superior to the previous system.
"I think we have a great platform to keep developing and making improvements so New Zealanders continue to get the world class tax system they deserve."
Find out more about Inland Revenue's changes at www.changingforyou.ird.govt.nz.