Reaching $100,000 invested sounds like a big milestone. But the truth is, it doesn't require winning the lottery or picking the next market darling. With consistency, patience, and compounding, investing $500 a month in ASX shares can get you there.
Here's how it works in four steps.

Image source: Getty Images
Step 1
The most important ingredient isn't timing the market. It's committing to investing every month.
At $500 per month, you're investing $6,000 per year. That might not seem life-altering at first, but what matters is how those contributions grow over time.
Assuming an average annual return of 9%, which is broadly in line with long-term historical share market returns, though never guaranteed, your portfolio starts to accelerate as compounding kicks in.
Step 2
Here's roughly what the journey could look like at a 9% average return:
After 5 years, you would have contributed $30,000, but your portfolio could be worth around $37,000.
After 10 years, you would have invested $60,000, and your portfolio could grow to approximately $95,000.
Somewhere before the 11-year mark, you would cross the $100,000 milestone.
But you don't have to stop there. After 15 years, your portfolio would be worth roughly $185,000, and after 20 years, it could be worth roughly $320,000 if everything went to plan.
Notice what happens over time. Compounding really starts to show its power the longer you make it work.
Step 3
To aim for long-term returns, the focus should be on quality ASX shares and exchange-traded funds (ETFs) rather than high-risk speculative stocks.
That could mean global leaders like ResMed Inc. (ASX: RMD), infrastructure-backed names like Goodman Group (ASX: GMG), or dominant platforms such as Xero Ltd (ASX: XRO). Alternatively, broad ETFs such as the iShares S&P 500 ETF (ASX: IVV) or the Vanguard MSCI International Index Shares ETF (ASX: VGS) can provide diversified exposure in a single trade.
The key is to invest in businesses or funds with competitive advantages and long growth runways.
Step 4
Reinvesting dividends can meaningfully boost long-term returns. It increases the number of shares you own, which then generates even more income and capital growth over time.
Just as importantly, avoid the temptation to stop investing during market downturns. Periods of weakness often provide opportunities to buy quality assets at lower prices.
Foolish Takeaway
Building $100,000 with $500 a month is about discipline.
By investing consistently, targeting quality ASX shares or ETFs, and allowing compounding to work over a decade or more, that six-figure milestone becomes far more achievable than it first appears. The sooner you start, the easier it gets.