It depends how you want to invest it. In most cases the best place to start is by visiting your bank. ASB, ANZ and Westpac have good options for fund management. There are also a number of Kiwisaver investment companies that offer direct to the public too such as:
If you have a small amount to invest I recommend going to your bank. If you have a larger amount $50,000+ I recommend visiting a couple of those larger fund managers to see what suits you. If you have even more money than that you should look to visit a financial adviser. AMP has them and high level ones are Forsyth Barr and JB Were or https://craigsip.com/
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