Should You Pay Down Your Home Loan or Invest? A Guide for Australian Tech Professionals

By Mo, Founder and Principal Adviser - My Wealth Choice, Sydney

There's a question that runs through almost every financial conversation in tech circles: when extra cash arrives - whether it's a quarterly RSU vest, an end-of-year bonus, or simply a month where you've managed to save well, where should it go?

Smash the mortgage? Fire it into the market? Top up super? The answer you've probably heard is "it depends." That's technically true, but it's also not very useful. So this guide gives you something better: a sequenced framework that respects how tech professionals actually earn money, what the Australian tax system actually does to that money, and how to build real wealth without flying blind.

If you're earning $250,000 or more through a combination of base salary, annual bonus, and RSUs - at a company like Atlassian, Canva, Google, Salesforce, Afterpay, or any of the dozens of other tech employers operating in Australia - this is written for you.

The First Principle That Cuts Through the Noise

Before we get into the details, here's the one idea that anchors everything:

Cash sitting in your home loan offset account earns a guaranteed, after-tax return equal to your mortgage interest rate.

If your mortgage rate is 6%, every dollar in your offset saves exactly 6% in interest - and you pay zero tax on that saving, because you're reducing a debt rather than earning income. That's your baseline. Every alternative use of money has to beat 6% after tax and after fees to be the smarter move.

That's the hurdle rate. Keep it in mind as we work through the rest.

First, Understand Your Income - All Three Parts of It

Most financial advice is written for people with one income stream. If you're in tech, you have three and each behaves differently.

Base salary is predictable, taxed at source via PAYG, and arrives fortnightly. Straightforward.

Annual bonus arrives once or twice a year, usually tied to performance, and is taxed as ordinary income at your marginal rate. It's the windfall that most people either blow on lifestyle or throw at the mortgage without thinking.

RSUs (Restricted Stock Units) are the wildcard. They vest on a schedule - typically quarterly or annually over four years - and are denominated in USD. For many tech workers, RSUs make up 20-40% of total compensation. But unlike cash, they arrive as shares, carry concentration risk, and have specific tax treatment that most people don't plan around properly.

Getting the strategy right means treating these three streams differently - not lumping them together as "income I'll figure out later."

The Australian Tax Reality: Higher Stakes Than You Realise

 Your Marginal Rate Is Likely 47%

If your total taxable income exceeds $190,000 - which is realistic once base, bonus, and RSU vesting income are combined - every extra dollar is taxed at 45 cents plus the 2% Medicare Levy. That's a 47% marginal rate.

This makes every decision tax-sensitive in a way that lower-income earners simply don't face. A 6% guaranteed return in your offset account is worth considerably more to you than it would be to someone on a 34% marginal rate.

RSUs: Taxed at Vest, Then Again When You Sell

This is the area where most tech workers leave the most money on the table - either through poor planning or simply not understanding the rules.

When your RSUs vest, the market value of the shares on the vesting date is assessed as ordinary income and taxed at your full marginal rate. Your employer will withhold tax automatically, typically by selling a portion of your vesting shares. So if $80,000 worth of RSUs vest on top of a $160,000 salary and a $20,000 bonus, your assessable income for that year is $260,000 - and your tax bill reflects that.

The critical follow-on: the 50% CGT discount.

After vesting, the shares have a cost base equal to what you were taxed on - their market value at vest. If you then hold those shares for more than 12 months before selling them, any capital gain from price appreciation is taxed at half your marginal rate under Australia's CGT discount. For someone on a 47% marginal rate, that means long-term gains are taxed at roughly 23.5% - a meaningful difference.

This creates a real incentive to think carefully about when you sell your vested shares, not just whether you sell them.

The Case for Paying Down the Mortgage

The argument for your mortgage is fundamentally about certainty.

Paying down your home loan at 6% earns you a guaranteed 6% return. No market risk, no volatility, no sequence-of-returns problem. In a world where equity markets can fall 20-30% in a bad year, the guaranteed return of a lower debt balance has real value - psychological and financial.

There's also a cashflow resilience argument that matters particularly in tech. The sector has seen significant layoffs in recent years, and high-income roles are not immune. A smaller mortgage means lower minimum monthly repayments and less pressure if your income changes suddenly. Financial stress is often a function of fixed obligations, not total wealth - and reducing your loan balance reduces that obligation permanently.

The Case for InvThe Case for Investingesting

The counterargument is equally strong: over long time horizons, diversified equity markets have historically delivered returns well above the risk-free rate.

The ASX 200 has delivered total returns averaging around 8-9% per annum over multi-decade periods. Global equities have done better than that over the past two decades. If your mortgage rate is 6%, a diversified portfolio earning 9% leaves you ahead on a simple comparison.

But the headline comparison misses some important nuance:

Investment returns are taxed. Dividends and capital gains are assessable income. At a 47% marginal rate, a 9% gross return can look considerably less impressive after tax - unless you're holding long enough for the CGT discount or structuring through super at 15%.

The comparison is asymmetric in risk. The 9% return is an average that includes years of significant losses. The 6% mortgage saving is guaranteed. If you're already carrying concentration risk in your employer's stock through RSUs - which most tech workers are - adding more equity exposure may not be the move.

The Concentration Risk Problem: RSUs Are Not an Investment Plan

Let's be direct about something the tech industry rarely says out loud: holding your RSUs is not investing. It is the absence of a decision dressed up as one.

RSUs are compensation. They are a mechanism your employer uses to align your incentives with company performance and to retain you. They are not a thoughtfully constructed investment portfolio. You did not choose this company based on its valuation, its competitive moat, or its risk-adjusted return profile relative to alternatives. You chose it because it was a good job. That is a completely different thing.

Yet thousands of tech professionals unconsciously treat accumulated RSU holdings as their investment strategy - and it fails on every dimension that matters:

There is no diversification. A sound investment portfolio spreads risk across dozens, hundreds, or thousands of companies, sectors, and geographies. Your RSU holding is a single stock. One earnings miss, one regulatory headwind, one strategic misstep by leadership, and your "investment" reprices overnight.

You are already maximally exposed to this company. Your income, your career progression, your professional reputation, and your daily working hours are all tied to one employer. Adding your savings to that same bet doesn't increase your upside - it multiplies your downside. If the company struggles, you face cuts to your bonus, risk to your employment, and a falling share price simultaneously. That is not a portfolio. That is concentration masquerading as wealth.

It happened to be passive, not intentional. You didn't decide to put $150,000 into a single tech stock. It accumulated because shares vested and you didn't sell. Inaction is not a strategy - and in this case, it's a strategy that most financial advisers would never recommend to a client who walked in off the street.

This is not a theoretical concern. Tech workers at Atlassian, Zip, Afterpay, Xero, and dozens of US-listed names experienced exactly this during the 2022 tech sell-off. Atlassian's share price fell more than 70% from its peak. RSU holdings that had looked impressive on paper were decimated - at precisely the moment companies were reducing headcount. People lost both their income security and their paper wealth in the same quarter.

The practical implication is clear: treat your vested RSUs as cash compensation that happens to arrive in share form. Once vested, sell them into a diversified portfolio - ideally after 12 months to access the 50% CGT discount - and stop thinking of your employer stock as "part of your portfolio." It isn't. It's deferred salary.

There are limited exceptions: pre-IPO situations with trading restrictions, or cases where your company stock is genuinely a tiny fraction of your overall net worth. For most tech workers receiving regular quarterly vests, neither applies.

The Offset Account: The Most Underrated Tool in Australian Personal Finance

Here's where the Australian financial system gives you something genuinely powerful - and where many high-income earners aren't being strategic enough.

A mortgage offset account is a savings or transaction account linked to your home loan. The balance in the account is subtracted from your outstanding principal when calculating your daily interest. If you owe $950,000 and have $100,000 in your offset, you pay interest on $850,000. Importantly, the money remains fully liquid - you can access it at any time.

The effective return is your mortgage rate: 6%, risk-free, after tax.

Compare that to a high-interest savings account offering, say, 5.2% before tax. At a 47% marginal rate, that's roughly 2.75% after tax. Your offset is earning more than twice that on every dollar - with the same liquidity and zero risk.

This is why the offset account is the cornerstone of the strategy, not a secondary consideration.

The Right Order of Operations

Rather than treating this as a binary choice, high-income tech professionals benefit from a sequenced approach. Here's the order that makes sense:

1. Build your offset buffer first.

Before directing surplus cash into investments, establish a meaningful buffer in your offset account. A useful target is 6-12 months of total living expenses plus mortgage repayments. For a household spending $120,000 per year, that's $60,000-$120,000. This earns you the best risk-adjusted return available, protects against income disruption, and keeps your options open.

Use your annual cash bonus to build and maintain this buffer. That's the highest-priority use of windfall cash.

2. Maximise concessional super contributions.

The concessional (pre-tax) contribution cap is $30,000 per year. If your employer contributes $18,000, you can salary sacrifice an additional $12,000. The tax benefit for someone at a 47% marginal rate is substantial: you're paying 15% tax inside super instead of 47% on your personal return. That 32-cent-in-the-dollar saving is one of the most powerful levers available to high-income earners, and it's frequently overlooked by tech professionals focused on their take-home pay.

Note: super is illiquid until your preservation age (currently 60). It complements your offset buffer - it doesn't replace it.

3. Manage RSUs deliberately, not by default.

Have a written policy for your RSUs rather than defaulting to holding or selling reactively. A sensible starting point for most people: sell company stock once you've held it for 12 months (to access the CGT discount), and redeploy proceeds into diversified assets. If your concentration in company stock is already high, sell sooner and accept the tax cost - the risk reduction is worth it.

4. Run a split between offset and investing.

Once your offset buffer is funded, direct surplus cash flow into a diversified investment portfolio using a consistent split. A reasonable starting framework:

Profile	Offset	Investing
Conservative (variable income, shorter horizon)	70%	30%
Balanced (stable dual income, 10+ year horizon)	50%	50%
Growth (high cash flow, high risk tolerance)	30%	70%

These ratios aren't permanent. Revisit them annually as rates, income, and life circumstances change.

5. Consider debt recycling once the structure is clean.

If you're investing consistently and want to improve tax efficiency, debt recycling allows you to convert non-deductible home loan debt into deductible investment debt over time. It's a useful strategy for disciplined investors - but it requires clean loan structure and consistent record-keeping. Don't introduce this complexity before your offset buffer and investment split are both well established.

 A Practical Example

Sarah is a senior product manager at a large tech company in Melbourne. She earns:

- $170,000 base salary

- $22,000 annual bonus

- $55,000 in RSUs vesting annually across quarterly schedules

Her total pre-tax income is around $247,000. Her marginal rate is 47%.

She has a $980,000 mortgage at a 6% variable rate, with $25,000 currently sitting in her offset.

Her priority order:

First, she uses her annual bonus to build the offset to $90,000 - six months of expenses and repayments for her household. That takes two years but earns her 6% risk-free on every dollar along the way.

Simultaneously, she salary sacrifices $12,000 into super annually, saving approximately $3,840 in tax each year she does this.

For her RSUs, she tracks the 12-month holding period on each quarterly vest and sells into VGS and VAS index funds once it's passed. She calculates what a 23.5% effective CGT rate (after the 50% discount) costs her versus holding for another year - and makes the call based on concentration at that point.

Once the offset hits $90,000, she switches her bonus to a 50/50 split: half into offset, half into a brokerage account investing in low-cost diversified ETFs.

Five years in, she has a meaningful buffer, a growing diversified portfolio, and company stock concentration that's well managed - instead of having accumulated $200,000+ in a single stock she's also dependent on for her income.

Common Mistakes to Avoid

Using redraw instead of offset. Redraw funds can contaminate the tax deductibility of your loan if you ever convert it to an investment property. Always park surplus cash in an offset account, not in the loan itself.

No buffer before investing. Markets are volatile. If you invest aggressively without a buffer and face unexpected costs or income disruption, you may be forced to sell at exactly the wrong time. The buffer comes first.

Holding RSUs by default. Not actively managing your employer stock concentration is a decision - usually the wrong one for people who already take employment risk at that company.

Changing strategy after every market headline. Pick a split, commit for at least 12 months, and review deliberately. The investor who stays systematic beats the one who optimises reactively.

Ignoring tax timing on RSUs. Plan your vesting income with your accountant before June 30, not after. Large vests can push your total taxable income significantly higher and affect Medicare Levy Surcharge thresholds, private health insurance obligations, and other income-tested measures.

Frequently Asked Questions

Does paying off the mortgage always beat investing?

In terms of risk, yes. In terms of expected long-run wealth, not necessarily. The offset gives you a guaranteed risk-free return and full liquidity. Investing offers higher expected returns with risk. For most tech workers, the right answer combines both - in sequence.

Should I sell my RSUs immediately when they vest?

Not automatically. The 12-month CGT discount is meaningful at a 47% marginal rate. Assess your concentration, weigh the tax benefit of holding versus the risk of holding, and make an active decision each vest - don't default in either direction.

Is salary sacrificing into super worth it if I still have a big mortgage?

Usually yes. The 32% tax gap between your marginal rate and the 15% super contributions tax is too powerful to ignore, even with a mortgage. Treat it as a parallel track, not a competitor to your offset.

What if interest rates fall significantly?

Your offset hurdle rate falls too, making investing comparatively more attractive. If rates drop to 5% or below, revisit your split and consider tilting more toward growth assets.

Where does debt recycling fit?

It's a technique to make your home loan interest tax-deductible by borrowing against your equity to invest, then using a clean investment sub-account. It's useful for disciplined investors with a stable structure. Introduce it after your offset buffer and consistent investment habit are both well established.

The Bottom Line

The mortgage versus investing debate is a false binary. For Australian tech professionals earning $200,000+ in base, bonus, and RSUs, the right answer is a sequenced strategy:

Build your offset buffer first. It's the best risk-adjusted return available to you - 6%, tax-free, liquid.

Maximise concessional super. The tax benefit is too large to leave on the table.

Manage your RSUs deliberately. Don't let concentration risk build by accident.

Then invest consistently with a split that suits your risk profile and horizon.

Your offset account is not a consolation prize for people who don't invest. It's a powerful financial tool that earns you a guaranteed return while protecting your options. Once it's funded, let the offset and a diversified portfolio work together - rather than treating them as opponents.

Whenever you're ready, here are a few ways I can help you read on where you stand, the fastest levers to pull, and whether property is your engine or your anchor. No BS. Just clarity.

1. Listen to my Podcast - real financial strategies for tech pros, no boring jargon.

2. The Wealth Byte Newsletter - quick, no-BS emails once a month.

3. Follow me on LinkedIn - over 5,000 tech pros already do.

4. Wealth Bytes - YouTube - bite-sized videos on investing, RSU, tax strategies, and building real wealth.

5. Work 1:1 with me - build a strategic, work-optional financial plan to retire early on 10-20k per month.

This article is general in nature and does not constitute personal financial advice. Tax rates and legislation referenced apply to the 2024-25 Australian financial year. Individual circumstances vary - consider speaking with a qualified financial adviser and tax accountant, particularly around RSU and equity compensation planning, before making significant financial decisions.

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