Who would win from a multi-rate GST in New Zealand: evidence from a QUAIDS model*

The merits of New Zealand moving away from its broad-based single-rate GST structure – particularly by removing GST on food – are often raised in public discourse and political campaigns. This paper investigates who would benefit from the introduction of a multi-rate GST structure in New Zealand and, in particular, whether reduced GST rates would be a more effective way of providing support to poorer households than New Zealand’s current income-tested tax credit approach. Behavioural simulation results from a QUAIDS model confirm previous findings that applying reduced GST rates to food and beverages would have a small progressive effect, but that richer households would benefit more than poorer households in aggregate terms. Meanwhile, reduced GST rates applied to recreational and cultural expenditure would have a regressive effect. Additional simulation results clearly show that the family tax credit is a far superior mechanism for providing support to poorer households than reduced GST rates. New Zealand should therefore maintain its current approach of a broad-based single-rate GST and income-tested tax credits.