It is the Inland Revenue's practice, in general, to not accept requests for reassessment.
From a legal perspective there is the option to do so under Section 113 of the Tax Administration Act, however this is at the Inland Revenue's discretion and they use that discretion to deny opening up a GST period that is already filed.
The Inland Revenue's logic on this is that they don't want the additional administration cost of opening GST periods previously filed by businesses.
The Inland Revenue have recently reiterated their communication on this topic and recommended any GST input claims be processed in the next GST return to be filed.
There are two common scenarios where this logic would not apply:
- Outside of the 2 year timeframe would require an adjustment under Section 113, or
- If GST for your business is already under investigation by the Inland Revenue. In that situation an adjustment may be processed as part of the wider outcome of that investigation by the Inland Revenue.