As I am being quoted - I've done some additional research with the latest rules - and a good reference for source material.
Here is a good primer on it from Deloitte.
https://www2.deloitte.com/nz/en/pages/tax-alerts/articles/gst-on-remote-services.html
And the NZ IRD :
http://taxpolicy.ird.govt.nz/public...upplies-remote-services-nz-resident-consumers
NZ GST (Goods and Services Tax - or sales tax) laws WERE very simple - they are for goods and services offered and consumed within New Zealand.
Of course, the internet's global reach screws with this, so as of October 2016, new rules were brought in for offshore companies providing
services to New Zealanders.
The offshore suppliers of remote services to private consumers will have a liability to register for New Zealand GST if certain supplies exceed the threshold of NZ$60,000 per annum.
This clause is known as the Netflix Tax locally, as it was Netflix who were advertising here in NZ and competing with local streaming services but avoiding GST that caused the change.
The rules collect GST on services and intangibles (including digital downloads) supplied remotely by an offshore supplier to New Zealand-resident consumers. Insurance and remote gambling services provided by offshore suppliers are also be caught by the new rules.
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The upshot IS that GST may be payable by offshore companies with NZ users, and if they are going so they should have a NZ GST number - which should be on each invoice/bill.