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Case Study: When You Are Just Short of 20% Deposit

14 March 20254 min readBy Jarrod Kirkland
Case Study: When You Are Just Short of 20% Deposit

Key Takeaways

  • 1While this case study uses 2023 examples, the principles remain exactly the same today.
  • 2Small deposit shortfalls can trigger disproportionately large penalty costs - being $2,400 short cost over $5,000 in fees.
  • 3Family gifts with proper documentation are the preferred solution for deposit shortfalls.
  • 4Always calculate your maximum purchase price based on available deposit before house hunting.
  • 5The lesson endures: being just under 20% deposit is one of the most expensive positions to be in.

This case study examines what happens when your deposit falls just short of the 20% threshold-and how a small shortfall can cost thousands in fees.

:::note Timeless Principles

While this case study uses examples from 2023, the underlying principles remain exactly the same today. Being slightly short of the 20% deposit threshold still triggers disproportionate costs, and the solutions-family gifts, timing adjustments, or negotiating purchase price-are just as relevant now. The specific numbers may differ, but the lesson endures: always calculate your deposit requirements carefully before making an offer.

:::

This case study examines Bill and Hillary, a couple whose home purchase offer was accepted at $800,000, but their deposit fell short of the ideal 20% threshold at 19.7%. They were "$2,400 short of the ideal 20% deposit."

The Cost of Low Equity

When buyers have less than 20% equity, lenders impose additional fees or interest rate increases-in this case, 0.25% added to the mortgage interest rate. The financial impact was substantial: "Bill and Hillary are going to have to pay an extra $5,632 in interest and/or fees because they are short on their deposit by $2,400." That's a cost of 234% relative to the shortfall amount-paying $5,632 extra because they were $2,400 short.

Proposed Solutions

Solution 1 – Credit Cards: Though borrowing $2,400 on a credit card at 20% interest would cost far less than the $5,632 low-equity penalty, banks view borrowed deposits negatively and may flag the application.

Solution 2 – Family Gifts: A formal gift certificate from family members is acceptable to lenders and avoids the penalty entirely.

Solution 3 – Delayed Payment: Waiting for the next pay cycle is viable if timing permits, though it depletes emergency savings reserves.

Recommendation

The article recommends prioritizing family assistance, followed by the delayed payment option. These approaches allow clients to "save the client over $5,000 in additional costs" while maintaining financial flexibility for settlement-related expenses.

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Frequently Asked Questions

What happens if Im just slightly short of a 20% deposit?

Being even slightly short of the 20% threshold can trigger disproportionately large costs. In this case study, being $2,400 short triggered low equity fees and a 0.25% interest rate increase, costing over $5,632 in additional interest and fees - a 234% penalty relative to the shortfall. Understanding [LVR requirements](/blog/what-does-lvr-mean) before making an offer is crucial.

Can I use a credit card to top up my deposit?

While mathematically borrowing $2,400 on a credit card at 20% interest would cost far less than a $5,632 low-equity penalty, banks view borrowed deposits very negatively. Using credit for your deposit may flag your application and could result in decline. Banks want to see genuine savings, not debt used to meet deposit requirements. Learn more about [how credit cards affect your lending](/blog/the-real-cost-of-credit-cards-on-your-mortgage-capacity).

Is a family gift the best solution for deposit shortfall?

A formal gift certificate from family members is an excellent solution that lenders fully accept. It avoids the low equity penalty entirely and demonstrates family support for your purchase. The gift must be properly documented with a signed gift certificate confirming the money does not need to be repaid, and the bank may verify the source of funds.

What other options exist for small deposit shortfalls?

Beyond family gifts, you could wait for the next pay cycle if timing permits (though this depletes emergency savings), negotiate a lower purchase price, or explore whether your KiwiSaver withdrawal can cover the gap. Each option has trade-offs - consult with a mortgage adviser to determine the best approach for your specific situation.

How can I avoid deposit shortfall situations?

Calculate your maximum purchase price based on available deposit before house hunting, leaving a buffer for unexpected costs. Use our [deposit savings calculator](/mortgage-tools/deposit-savings-calculator) to plan ahead. Remember that [your deposit needs](/blog/how-much-deposit-do-you-need-to-buy-your-first-home) include not just the 20% but also legal fees, building inspections, and moving costs.

Does low equity margin affect all banks equally?

Different banks have varying approaches to low equity lending and associated fees. Some may offer better terms for borrowers just under the 20% threshold, while others are stricter. A mortgage adviser can help identify which lenders offer the best options for your specific deposit situation and potentially save thousands in fees.

What is the long-term cost of accepting low equity terms?

Low equity fees and rate increases compound over the life of your mortgage. A 0.25% rate increase on an $800,000 mortgage over 30 years represents tens of thousands in additional interest. It is almost always worth finding the extra deposit money or adjusting your purchase price to avoid these long-term costs.

Disclaimer

The information on this website is for general guidance only and does not constitute financial or investment advice. Always do your own research and seek personalised advice from a qualified financial adviser or mortgage adviser before making financial decisions. All investments carry risk and past performance is not indicative of future results.

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