The New Zealand dollar jumped more than one US cent after the Federal Reserve was more cautious than expected about a revival in the US economy and the outlook for interest rate rises.
The kiwi rose as high as 75.22 US cents, from 73.75 cents ahead of the Fed's statement released at 7am New Zealand time.
The local currency was trading at 74.34 US cents at 8am in Wellington, from 73.03 cents at 5pm yesterday.
The trade-weighted index increased to 78.18 from 77.22 yesterday.
The US dollar index, which measures the greenback against a basket of currencies, dropped to its lowest in more than a week after the Federal Open Market Committee lowered its outlook for growth, inflation and interest rates, offsetting the impact of removing the key word 'patient' from its statement which signals it is prepared to raise rates based on future economic data.