When managing a larger mortgage in New Zealand, the "best" bank goes beyond just chasing the absolute lowest advertised fixed interest rate. For substantial loans, features like mortgage structuring flexibility, offset facilities, multi-account linking, and cash contributions (cashback) become far more critical to minimizing long-term interest.

Key Features to Look for with a Larger Mortgage

1. Robust Offset & Revolving Credit Facilities

   • With a large mortgage, saving even a few thousand dollars in interest makes a massive difference. Look for banks that allow you to split your mortgage—locking a portion into competitive fixed rates while keeping a flexible chunk in an offset mortgage or revolving credit.
   • Multi-account and family linking: Some major banks allow you to link multiple checking, savings, or even family members' accounts (such as parents or children) to offset against the loan balance.

2. Cashback and Settlement Contributions

   • On larger loan amounts (typically over NZ$500,000 to NZ$1,000,000+), major Tier 1 banks often compete aggressively for your business by offering substantial cashback incentives (sometimes expressed as a percentage of the total loan draw-down, subject to bank policy and a minimum term lock-in).

3. Complex Lending and Discretionary Serviceability

   • Major lenders handle high-value lending differently. If your mortgage is large due to bridging finance, multiple investment properties, or complex self-employed/trust income structures, you need a bank with dedicated high-net-worth or private wealth tiers (such as ANZ, BNZ, or ASB) that can offer customized credit policies.

How Major New Zealand Banks Compare for Large Mortgages

• BNZ (Bank of New Zealand):
  • Standout Feature: Their TotalMoney offset package is widely regarded as one of the best for large/complex setups because it allows you to link up to 50 everyday or savings accounts—including accounts belonging to extended family members (like parents or children)—maximizing your daily interest savings.
• Westpac:
  • Standout Feature: Strong Choices Offset and revolving credit integration. They offer smooth splitting capabilities and competitive matching on cashbacks for high-value borrowers shifting large lending books.
• Kiwibank:
  • Standout Feature: As a locally state-owned Tier 1 bank, they provide flexible offset products allowing you to link up to eight accounts. They are often very competitive on special fixed rates for quality borrowers.
• ANZ & ASB:
  • Standout Feature: As the largest retail banks by book size, they excel in large-scale property portfolios, fast turnaround on pre-approvals, and robust relationship-banking structures for high-value clients.

Recommended Action Plan

1. Request Formal Mortgage Tenders: Do not accept standard advertised rates. Approach at least two or three major banks (e.g., BNZ, ANZ, or Westpac) through a mobile mortgage manager or an independent mortgage broker to bid for your business using your total lending size as leverage.
2. Negotiate Cashbacks: Ask explicitly what cash contribution or legal fee subsidy they will provide upfront for moving or establishing a large mortgage book.
3. Optimize Your Loan Structure: Split your mortgage. Fix a safe majority (e.g., 70–80%) across preferred terms (such as 1-year or 2-year fixed) to protect against rate volatility, and place the remainder into an offset facility to absorb spare cash and savings.

Are you looking to structure your mortgage using an offset/revolving setup, or are you primarily focused on negotiating the lowest fixed rate and cashback offer?