Safe Withdrawal Rates for New Zealand Retirees

You've spent decades building your KiwiSaver and other savings. Now you're facing retirement and the question that keeps you up at night: how much can I safely withdraw each year without running out of money?

If you've done any research, you've probably heard about the 4% rule. It's the most famous retirement withdrawal strategy in the world. Withdraw 4% of your portfolio in year one, adjust for inflation each year after, and your money should last 30 years.

But here's the thing: the 4% rule was developed in the United States in the 1990s. It assumes you're relying entirely on your own savings for retirement income. It doesn't account for NZ Super, New Zealand's tax system, or the fact that as a Kiwi retiree, your financial picture looks fundamentally different from an American's.

So does the 4% rule work in New Zealand? And if not, what does?

The 4% rule emerged from research by financial planner William Bengen in 1994. He analyzed historical US market data going back to 1926 and found that a retiree could withdraw 4% of their initial portfolio balance (adjusted for inflation each year) and have their money last at least 30 years, even through major market crashes like the Great Depression.

It's elegant, simple, and has become the default rule of thumb for retirement planning worldwide. But it was built on several assumptions that don't hold in New Zealand:

• No guaranteed government pension: The 4% rule assumes your portfolio is your only income source. In New Zealand, NZ Super provides around $27,664 per year for a single person living alone (after-tax, 2024 rates), or $42,650 for a married couple. That's substantial income you don't need to withdraw from savings.
• Different tax structures: The US has capital gains taxes, New Zealand generally doesn't (except for investment properties and some shares). This affects how you think about portfolio withdrawals and asset location.
• US-centric asset allocation: Bengen's research used a 50/50 portfolio of US stocks and bonds. New Zealand retirees often hold different asset mixes, including more international diversification and potentially property.
• Social Security timing: Americans can claim Social Security as early as 62 or delay until 70, with significant benefit differences. In New Zealand, you're eligible for NZ Super at 65 (currently), with no early or delayed claiming options that change the amount.

None of this makes the 4% rule wrong. It just means blindly applying it to your New Zealand retirement might leave money on the table, or worse, give you false confidence in an inappropriate strategy.

Let's look at a practical example to understand why NZ Super changes your safe withdrawal rate.

Imagine you're a single retiree who wants to spend $60,000 a year in retirement. Here's how different scenarios play out:

Scenario A: Pure self-funding (4% rule approach)
You need a portfolio of $1.5 million to withdraw $60,000 per year at 4%. Your entire retirement depends on this portfolio lasting.

Scenario B: NZ Super plus personal savings (New Zealand reality)
You receive $27,664 from NZ Super. You need to withdraw $32,336 from personal savings to reach your $60,000 target. If you have a $500,000 portfolio, you're withdrawing 6.5% in year one. That's well above the 4% rule, but is it actually riskier?

Counterintuitively, Scenario B might actually be safer despite the higher withdrawal rate. Here's why:

• NZ Super is government-guaranteed, indexed to inflation, and continues for life regardless of market performance
• Your personal savings only need to cover about 54% of your retirement spending
• If markets crash and you need to reduce spending, you can make much smaller cuts because you have that NZ Super floor
• In the worst case, if your personal savings run out entirely, you still have $27,664 per year to live on

This is the fundamental insight: when you have a guaranteed income floor, you can afford to take more risk with the portion above it.

While there's less published research specific to New Zealand compared to the US, financial planners and researchers have adapted withdrawal rate studies to account for guaranteed pension income.

The key finding: when you have a pension covering a significant portion of expenses, you can potentially withdraw 5-6% or even higher from personal savings while maintaining similar failure rates to the traditional 4% rule applied to a larger portfolio.

Why? Because the guaranteed pension acts as a bond-like allocation that never runs out. If you were to think of NZ Super as part of your total retirement portfolio, it would represent a massive, inflation-protected, government-backed bond that pays out for life. This "asset" allows your actual investment portfolio to be more aggressively positioned or more heavily drawn down.

However, this comes with important caveats about sequence of returns risk and market timing, which we'll address shortly.

New Zealand's tax system creates different withdrawal considerations compared to the US:

No capital gains tax (mostly): In the US, retirees carefully manage capital gains because they're taxed at special rates. In New Zealand, you generally don't pay tax on capital gains from selling shares or managed funds (except for some foreign investments held less than certain periods). This means you have more flexibility in how you structure withdrawals.

PIE tax advantages: Portfolio Investment Entities (PIEs) like most KiwiSaver funds have capped tax rates. If your income is low enough, you might pay just 10.5% tax on PIE income versus higher rates on other income. For retirees with modest incomes from NZ Super plus small withdrawals, this can be valuable.

Progressive tax brackets: According to Inland Revenue's tax rate structure, you pay 10.5% on income up to $14,000, then 17.5% from $14,001 to $48,000, then 30% from $48,001 to $70,000. For a couple both receiving NZ Super ($42,650 combined), you're already partway up the tax brackets before withdrawing anything from savings.

No required minimum distributions: The US forces retirees to withdraw minimum amounts from retirement accounts starting at age 73. New Zealand has no such requirement. Your KiwiSaver and other investments can stay invested as long as you want (though you can access KiwiSaver from age 65). This gives you flexibility to delay withdrawals in down markets.

The practical implication: you might structure your withdrawal strategy around keeping your total income (NZ Super plus withdrawals) below certain tax thresholds, particularly the jump from 17.5% to 30% at $48,000 for individuals, or the jump to 33% at $70,000.

Rather than prescribing a specific number (which would be inappropriate without knowing your situation), here's a framework for thinking about what might work for you:

Step 1: Calculate your NZ Super coverage ratio

What percentage of your desired retirement spending does NZ Super cover? If you want to spend $60,000 and NZ Super provides $27,664, that's 46% coverage. The higher this ratio, the more flexibility you have with personal savings.

Step 2: Consider your time horizon

The 4% rule was designed for 30-year retirements. If you're retiring at 65 and planning to 95, that's the target. Earlier retirement means you might want to be more conservative. Later retirement (say, 70) might allow higher withdrawal rates because your time horizon is shorter.

Step 3: Assess your flexibility

Can you reduce spending in down markets? Do you have part-time work options? Could you downsize your home? The more spending flexibility you have, the more withdrawal risk you can take. Conversely, if your spending is fixed (mortgage, health costs), you'll want to be more conservative.

Step 4: Understand your portfolio

The 4% rule assumed a balanced 50/50 portfolio. If you're holding more conservative investments, you might need a lower withdrawal rate because expected returns are lower. More aggressive allocations might historically support higher withdrawal rates but with more volatility risk.

Step 5: Account for sequence risk

Your safe withdrawal rate isn't just a number, it's a number plus a strategy. If you retire into a bull market, you might successfully withdraw 6-7%. If you retire into a major crash, even 4% might be too aggressive. Consider dynamic withdrawal strategies that adjust based on portfolio performance.

Many financial planners now advocate for dynamic withdrawal strategies rather than rigidly sticking to a percentage. Here are approaches some New Zealand retirees consider:

The guardrails approach: Set upper and lower bounds for your withdrawal rate (say, 4-6%). In good market years when your portfolio is above target, withdraw at the higher rate or take one-off lump sums. In poor years when your portfolio drops, pull back to the lower rate or even skip inflation adjustments.

The floor-and-upside approach: Treat NZ Super as your floor spending. All personal savings withdrawals are "upside" that you can adjust based on market conditions. In great years, spend more on travel or gifts. In poor years, tighten the belt and live closer to your NZ Super amount.

The bucket approach: Divide your portfolio into time-based buckets (1-3 years in cash, 4-10 years in bonds, 10+ years in growth assets). Withdraw from the cash bucket, refilling it from other buckets only when markets are favorable. This helps avoid selling growth assets at the worst times.

The percentage-of-portfolio approach: Instead of withdrawing a fixed inflation-adjusted dollar amount, withdraw a fixed percentage each year. If your portfolio is $500,000 and you withdraw 5%, that's $25,000. If it grows to $600,000, you withdraw $30,000. If it drops to $400,000, you withdraw $20,000. Your spending automatically adjusts to portfolio performance.

Each approach has trade-offs. The key insight is that a rigid, set-it-and-forget-it withdrawal rate may not be optimal for New Zealand retirees who have the flexibility of NZ Super as a spending floor.

Misconception 1: "The 4% rule guarantees my money will last"

No withdrawal rate guarantees anything. The 4% rule had a roughly 95% success rate in historical US data. That means 5% of the time, retirees still ran out of money. And past performance, as they say, doesn't guarantee future results. Lower future returns could mean lower safe withdrawal rates.

Misconception 2: "I can set my withdrawal rate once and forget about it"

Market conditions change, your spending needs change, tax rules change, and NZ Super rates change (they're adjusted annually). Your withdrawal strategy needs periodic review, ideally with a financial adviser who understands your complete picture.

Misconception 3: "A higher withdrawal rate is always riskier"

Context matters. Withdrawing 6% from $500,000 while receiving $27,664 from NZ Super might be safer than withdrawing 4% from $1.5 million with no pension. The total portfolio longevity math is different when you have guaranteed income.

Misconception 4: "Safe withdrawal rates are just about portfolio returns"

Inflation, taxes, fees, and spending flexibility all matter as much as investment returns. A 5% withdrawal rate from a low-fee portfolio with flexible spending might outlast a 4% withdrawal rate from a high-fee portfolio with rigid spending needs.

Misconception 5: "NZ Super will definitely be there, so I can rely on it completely"

While NZ Super is currently government-guaranteed and politically popular, it's worth noting that the eligibility age has already been raised from 60 to 65 over past decades. Future changes could include means testing, different indexation, or further age increases. A prudent retirement plan doesn't put all eggs in the NZ Super basket, but it's reasonable to include it in your planning.

If you're planning retirement in New Zealand, here are the key implications:

1. Calculate what you actually need from savings

Don't just think about total retirement income. Think about the gap between NZ Super and your desired spending. That gap is what your personal savings need to cover, and it's likely smaller than you think.

2. Consider your complete financial picture

Your safe withdrawal rate depends on your mix of NZ Super, KiwiSaver, other investments, potential part-time work, home equity, and spending flexibility. It's not a one-size-fits-all number.

3. Plan for flexibility

Build some spending flexibility into your retirement plan. The ability to spend less in down markets dramatically improves portfolio longevity. This might mean maintaining a lower fixed expense base with discretionary spending on top.

4. Don't blindly apply overseas rules

The 4% rule, US tax strategies, and American retirement planning wisdom might not translate directly to New Zealand. Seek advice from professionals familiar with the New Zealand retirement landscape.

5. Run the numbers for your situation

Online retirement calculators can help you model different withdrawal rates and scenarios. Tools that account for NZ Super and local tax settings will give you more relevant results than generic international calculators.

For personalized guidance on your retirement withdrawal strategy, including how your specific savings, NZ Super entitlement, and spending goals interact, consider speaking with a licensed Financial Advice Provider who can assess your individual circumstances.

This article is general information only and does not constitute personalised financial advice. For advice tailored to your situation, speak with a licensed Financial Advice Provider. You can find a registered adviser at fma.govt.nz.