Westpac introduced a number of special term deposit rates available for a limited time for its two, three, four and five year rates. The new rates will all be the highest in their respective categories for banks and apply for term deposits of at least NZ$5,000.

Westpac put up its 5 year rate by 130 basis points (bps) to 6%. The new rate sits 85 bps higher than its highest bank competitor, Kiwibank. Its four year rate was pushed up 105 bps to 5.75%, 75 bps above Kiwibank's 5%. Westpac's new three year rate is 5.5%, up 80 bps, and 75 bps above Kiwibank's offering. The new two year rate has been raised by 75 bps to 5.25%, 25 bps above ASB's 5% rate. See all the rates here.

Westpac said the offer would be open until March 12.

"The rates will benefit many of our customers who are savers but who have seen their interest incomes reduce significantly in the past six months," Westpac spokesman Craig Dowling said.

"Also, successful retail deposit raising though such initiatives will contribute to Westpac's ongoing determination to support consumer and business borrowers, in turn helping to promote growth in the economy," Dowling said.