I’m sharing my investments for others planning how to become a millionaire in 10 years. I did it through consistent index fund investing, aggressive savings, and dollar-cost averaging. Starting at age 22 with $5,000 in the bank and a $55,000 salary, I reached $1,080,000 by age 32—without crypto gambles or inheritances, and in a high-cost-of-living (HCOL) city.
Here’s exactly how I did it—the real numbers, platforms, mistakes, and the millionaire investing strategy you can replicate today.
How to Become a Millionaire: My Starting Point and First Investment
Where I started at 22: $55k salary and $5k in the bank
At 22, I graduated with an Economics degree, landed my first corporate job paying $55,000 annually, and had $5,000 in the bank. No student loan debt, but no safety net either.
My first corporate job was overwhelming. Office politics, chaos, and the realization I’d be running this 9–5 race for 40+ years until retirement.
I had to shift my mindset: the wealthy make their money work through investments. I needed to copy what rich people do.
But where to start?:
- I knew nothing about stocks or bonds
- Didn’t understand mutual funds vs ETFs
- Had no idea what “asset allocation” meant
- Didn’t know where to go to start investing
P.S. if you’re a beginner investor, check out my ultimate guide to investing and building wealth for a comprehensive overview of everything you need to know to get started (risk tolerance, account types, tax implications, stocks, bonds, index funds, common mistakes, etc).
Why I chose Betterment as my first investing platform at age 23
At 23, I discovered robo-advisors and joined Betterment. The appeal: start investing without needing to know anything.
Betterment removed the intimidation factor. I answered questions about risk tolerance, made my initial deposit, and the platform automatically invested in U.S. stocks, international stocks, and bonds. The 0.25% annual fee seemed worth it for automation and peace of mind.
Looking back, Betterment was perfect training wheels. Sometimes the best investment strategy is simply the one you’ll actually stick with. Especially for beginner investors, Betterment is one of the best platforms to get started with easy and automated investing.
What my income looked like from 22 to 32 years old
My salary progression was aggressive through job-hopping and earning my MBA through part-time night and weekend classes, going to school while working full-time:
- Age 22: $55,000 starting salary (to be honest, I thought I was already rich then)
- Age 23: Job hopped for a pay jump, and earned two promotions
- Age 25: First six-figure salary after MBA (I moved across the country to get it)
- Age 25-32: Continued increases through promotions and internal moves
Each raise went straight into investments, not lifestyle upgrades. When my salary increased $10,000, my monthly investments increased proportionally.
By age 30, our household net worth hit $1 million ($800k from me, $200k from my wife). My individual net worth crossed $1 million at age 32.
What Investment Strategy Made Me a Millionaire in 10 Years?
How much did I invest each month to reach $1 million?
I invested 30-50% of my net income consistently across 10 years:
| Salary Level | Average Monthly Investment | Average Annual Investment |
|---|---|---|
| $55,000 starting (Age 22-25) | $2,000 | $24,000 |
| $110,000+ (Age 25+) | $5,000+ | $60,000+ |
The reality: I contributed $500k-$600k of my own money. The remaining $400k-$500k came from investment returns, compound interest, and company matches.
My Account Priority:
- Max out 401k employer match
- Fully fund Roth IRA
- Taxable brokerage for additional savings
What is dollar-cost averaging and why it powered my wealth?
Dollar-cost averaging means investing a fixed amount at regular intervals regardless of market conditions. I set up automatic monthly transfers so the money moved without me thinking.
This removed all emotion. During the March 2020 crash when the S&P 500 dropped 34%, my automatic contributions kept buying discounted shares. I never tried timing the market.
Why It Works:
- Removes emotional decision-making
- Buys more shares when prices are low
- Averages out cost per share over time
- Forces consistency through all conditions
The system ran on autopilot. I never had to decide “should I invest this month?”
Should you use a robo-advisor or manage investments yourself?
I started with Betterment’s 0.25% fee because I knew nothing—the right call initially. But once I understood index funds, the fee felt unnecessary.
Fee Impact:
| Portfolio Balance | Annual Fee (0.25%) | 10-Year Cost |
|---|---|---|
| $50,000 | $125 | ~$1,500 |
| $200,000 | $500 | ~$7,000 |
| $500,000 | $1,250 | ~$20,000 |
In 2020, I moved to Fidelity for zero-expense-ratio index funds, and to consolidate all my investments (including my company’s 401k and HSA) in one place.
Use Robo-Advisors When:
- Completely new to investing
- Paralyzed by decisions
- Portfolio under $50,000
DIY Invest When:
- Understand index fund basics
- Portfolio exceeds $100,000
- Want to minimize fees
You can start investing in 6 steps with my beginner’s roadmap.
How I Built Wealth with Index Fund Investing (Years 1-5)
What investments did Betterment choose for my portfolio?
Betterment automatically allocated based on my aggressive risk tolerance:
My Portfolio:
- ~70% U.S. Stocks (VTI)
- ~20% International Stocks (VEA)
- ~10% Bonds (AGG)
This passive approach meant owning thousands of companies without researching individual stocks. While some underperformed, tech giants generated massive returns that carried the portfolio higher.
What were my actual investment returns from age 22-27?
From 22 to 27, my net worth grew from $5,000 to $204,000 — a $199,000 increase. But aggressive contributions drove most growth, not returns alone.
Net Worth Growth (Years 1-5):
| Age | Year | Net Worth | Annual Increase |
|---|---|---|---|
| 22 | 2013 | $5,000 | (Year 0) |
| 23 | 2014 | $28,000 | $23,000 |
| 24 | 2015 | $65,000 | $37,000 |
| 25 | 2016 | $112,000 | $47,000 |
| 26 | 2017 | $169,000 | $57,000 |
| 27 | 2018 | $204,000 | $35,000 |
I was depositing $20K-$60K annually. Investment returns added 20-30%, but the heavy lifting came from disciplined saving.
You won’t get rich from returns alone early on. You get rich by saving aggressively and letting compound interest work over your lifetime.
For beginners, I recommend investing in ETFs and specifically broad market index funds that follow the S&P 500 (I give my top picks in this article).
How did my rental property income accelerate wealth building?
By 27, a rental property I house-hacked (I lived in the primary bedroom and rented the two guest rooms) helped triple my net worth since first buying it at 24 years old. The rental income got reinvested into stocks.
Real Estate vs Stocks:
| Investment | Annual Return | Maintenance | Liquidity |
|---|---|---|---|
| S&P 500 Index | 10-12% | None | High |
| Rental Property | 6-8% | Moderate-High | Low |
Although stocks remained my core wealth-building engine, real estate provided diversification and cash flow. I bought my first house for just 10% down, a 4.125% interest rate, and a $986 monthly mortgage payment (excluding property taxes and home insurance, which I paid separately).
The best part was I was able to live here almost completely free through rental income. My two guest rooms rented for $600 and $650 each, bringing in $1,250 a month in rental income.
But still, index fund investing generated the majority of my millionaire status.
How Compound Interest and Dollar-Cost Averaging Accelerated My Growth (Years 6-10)
When did I switch from Betterment to Fidelity and why?
In 2020, I moved everything from Betterment to Fidelity for three reasons:
- Consolidation – Same platform as my 401(k) and HSA meant simplification and easier tracking
- Cost Reduction – Eliminate 0.25% fee
- Control – Now that I was comfortable with investing, I wanted to determine my own portfolio
By my late 20s, I understood S&P 500 index funds would capture market returns without constant monitoring. I also felt that, although Betterment’s robo-advised portfolio was diversified and safe, it was more conservative than necessary. I was young, had solid emergency savings, and had a greater risk tolerance once I was confident and more knowledgeable about stocks.
But, I did keep my high-yield savings account at Betterment, called the Betterment Cash Reserve. And I still recommend Betterment as one of my top 7 best investing apps for beginners. Without Betterment, I don’t think I would have ever invested outside of my company 401(k).
What is FNILX and why I chose this S&P 500 fund
FNILX is Fidelity’s zero-expense-ratio S&P 500 mutual fund tracking America’s 500 largest companies. In my mid-20s, I simplified my investments across my Roth IRA, HSA, and taxable brokerage by investing exclusively in this fund.
Key Features:
- 0.00% expense ratio
- $0 minimum investment
- Holdings: 500+ large-cap U.S. stocks
Fee Comparison Over 30 Years:
| Fund | Expense Ratio | Cost on $500K |
|---|---|---|
| FNILX | 0.00% | $0 |
| Typical Index | 0.05% | ~$30,000 |
| Active Fund | 0.75% | ~$300,000 |
One fund, automatic contributions, zero maintenance. I bet on American businesses and capitalism continuing to grow.
How did compound interest turn $100k into $1 million?
By age 25, I had my first six-figures at $112,000. That early capital compounded for seven more years.
Early Money Works Harder:
| Investment Age | Amount | Years Growing | Value at 32 (10%) |
|---|---|---|---|
| Age 23 | $10,000 | 9 years | $23,579 |
| Age 26 | $10,000 | 6 years | $17,716 |
| Age 29 | $10,000 | 3 years | $13,310 |
| Age 31 | $10,000 | 1 year | $11,000 |
The acceleration in years 6-10 was dramatic:
Net Worth Explosion:
| Age | Year | Net Worth | Annual Increase |
|---|---|---|---|
| 28 | 2019 | $300,000 | $96,000 |
| 29 | 2020 | $500,000 | $200,000 |
| 30 | 2021 | $805,000 | $305,000 |
| 31 | 2022 | $824,000 | $19,000 |
| 32 | 2023 | $1,080,000 | $256,000 |
My net worth increased by $876,000 from age 27 to 32, or an average of $175,000 per year. While 2022 was a down year for the stock market (about -20% returns for the S&P 500), continuing to make investment contributions and maintaining my holdings helped my portfolio return to strong growth the following year. Compound interest did the rest of the heavy lifting.
Why did I switch to VOO in 2024 for better tax efficiency?
Starting in 2024, I redirected new contributions to VOO (Vanguard S&P 500 ETF) for better tax efficiency. FNILX distributes more dividends, creating taxable events.
FNILX vs VOO:
| Feature | FNILX | VOO |
|---|---|---|
| Expense Ratio | 0.00% | 0.03% |
| Tax Efficiency | Good | Excellent |
| Dividends | Possible | Rare |
I kept my existing FNILX shares to avoid triggering capital gains taxes. New money goes into VOO for better tax treatment.
What Investment Mistakes Did I Make and How to Avoid Them?
Mistake #1: Opening a Roth IRA at Bank of America without choosing investments
At 23, I deposited money into a Roth IRA at Bank of America without selecting investments. Cash sat earning nothing for nearly a year.
The Damage:
- Lost potential: $500
- While this doesn’t seem like a lot, $500 compounded at 10% returns over 40+ years would have grown to over $22,000 by retirement (ouch)
- Lesson: Opening an account ≠ investing
Remember you must select specific investments after you open an account. The account is just a container. Once I realized this, I transferred my Roth IRA to Betterment and let the robo-advisor choose my portfolio.
Mistake #2: Choosing an overly conservative 401(k) target-date fund
At 22, I selected a conservative target-date fund (I think it was the Fidelity Freedom 2055 Fund) designed for someone near retirement, not for someone with 40 years to grow.
Impact Over 10 Years:
| Allocation | Returns | Lost Opportunity |
|---|---|---|
| Conservative (60/40) | ~6-7% | Baseline |
| Aggressive (90/10) | ~10-11% | ~$40,000 |
I eventually moved to a large cap index fund (and ETF that follows the S&P 500) when I switched employers and received advice from a more senior manager. If I’d done this from day one, I’d have reached millionaire status faster.
Mistake #3: Not knowing about Backdoor Roth IRA contributions
After exceeding Roth IRA income limits at 27, I stopped contributing for a year. I didn’t know about the Backdoor Roth IRA strategy.
How a Backdoor Roth IRA Works:
- Contribute cash to Traditional IRA (no income limits)
- Immediately convert that cash to Roth IRA
- Once the cash is settled in your Roth IRA, trade it for your investment of choice (e.g. VOO)
- Money grows tax-free forever, providing tax-free income in retirement
The Cost: That missed $6,000 could’ve grown to $168,000+ by retirement at 10% annual returns.
(Side note: calculating the costs of your mistakes is not the best pick-me-up.)
Mistake #4: Leaving employer 401(k) match in declining company stock
My employer’s 401k match auto-invested in company stock. I didn’t realize I could rebalance for nearly two years while the stock declined.
What Happened:
| My Contributions | Employer Match |
|---|---|
| S&P 500 (positive 10-12%) | Company Stock (negative 10-12%) |
A chance hallway conversation with a coworker revealed I could move employer contributions to other investments of my choosing at any time. By then, nearly two years of value was lost.
Lesson: Actively manage retirement accounts. Review allocations quarterly.
What other investing mistakes cost me money in my 20s?
Additional Costly Errors:
- Emotional investing – Sold during downturns, missed recoveries
- Didn’t max tax-advantaged accounts – Left tax savings on table
- Lifestyle creep – Let spending increase with raises
- Learned too slowly – 2-3 personal finance books would’ve saved thousands
Successful investing is 80% behavior, 20% investment selection.
For more common problems and questions from beginners, see my list of 19 investing for beginner FAQs.
Millionaire Investing Strategy: My Actual Returns and Your Action Plan
What were my average annual investment returns over 10 years?
My returns averaged 10-12%, matching historical S&P 500 performance. But returns varied wildly year-to-year.
Market Reality:
| Year | Condition | Return |
|---|---|---|
| 2013-2017 | Bull Market | 12-20% |
| 2018 | Correction | -5% |
| 2020 | COVID Crash/Recovery | +18% |
| 2022 | Bear Market | -18% |
| 2023 | Recovery | +26% |
In March 2020, my portfolio dropped 30%+. But I maintained automatic contributions, bought discounted shares, and the portfolio recovered within months.
Key Truth: You will experience losses. The S&P 500 has always recovered and reached new highs over long periods.
Time in the market beats timing the market.
How much of my net worth was from investment returns vs savings?
Net Worth Breakdown:
| Source | Amount | Percentage |
|---|---|---|
| Personal Contributions | $500k-$600k | 55-60% |
| Investment Returns | $400k-$500k | 40-45% |
| Total | $1,080,000 | 100% |
Both matter equally. You can’t reach seven figures through returns alone without aggressive contributions.
The Formula:
Consistent contributions (30-40% of income)
+ Long time horizon (10+ years)
+ Market returns (8-12% annually)
+ Tax-advantaged accounts
+ Staying invested through volatility
= Wealth
By age 29-32, my net worth was increasing by $200K-$300K annually, largely from compound interest.
What would I do differently if I started over today?
5 Critical Changes:
- Tax-advantaged accounts first – Max 401k match, Roth IRA, learn Backdoor Roth early
- Skip robo-advisors – Go straight to Fidelity, invest in S&P 500 index funds
- Automate investment increases – Raise contribution $400 for every $5,000 salary increase
- Proper 401k allocation – 90% stocks, 10% bonds from day one
- Educate faster – Read “Simple Path to Wealth,” Bogleheads philosophy, r/financialindependence
These changes would’ve accelerated my path by 1-2 years and saved thousands in fees.
How can you replicate my millionaire investing strategy?
Your 7-Step Action Plan:
Step 1: Open Investment Accounts
| Brokerage | S&P 500 Fund | Expense Ratio | Minimum |
|---|---|---|---|
| Fidelity | FXAIX | 0.015% | $0 |
| Vanguard | VOO | 0.03% | 1 share |
| Schwab | SWPPX | 0.02% | $0 |
Choose one fund. Invest exclusively in it.
Step 2: Set Up Automatic Contributions
| Annual Income | Monthly (30-40%) | Annual Total |
|---|---|---|
| $50,000 | $1,250-$1,667 | $15,000-$20,000 |
| $75,000 | $1,875-$2,500 | $22,500-$30,000 |
| $100,000 | $2,500-$3,333 | $30,000-$40,000 |
Start with what you can afford. Increase with every raise.
Step 3: Priority Order
- Employer 401k match (free money)
- HSA up to $4,300 (2025 limit)
- Roth IRA up to $7,000 (2025 limit)
- Max 401k to $23,500 (2025 limit)
- Taxable brokerage for excess cash flow
Step 4: Maintain 6-Month Emergency Fund
Keep emergency savings in high-yield accounts earning ~4-5%:
- Betterment Cash Reserve (I did keep Betterment for my HYSA)
- Marcus by Goldman Sachs
- Ally Bank
- American Express Savings
Step 5: Stay Invested 10+ Years
The S&P 500 has delivered positive returns over every 10-year period in history.
During Crashes:
- Keep automatic contributions running
- Buy discounted shares
- Turn off financial news
- Review quarterly, not daily
Step 6: Target 30-50% Savings Rate
This aggressive rate separates millionaires from average savers. It can also drive your FIRE (Financial Independence, Retire Early) journey.
Step 7: Live Below Your Means
- Affordable housing
- Cook at home
- Drive used cars
- Cut unused subscriptions
- Focus on income increases
Ultimately, my millionaire investing strategy wasn’t complicated or revolutionary.
It was boring. Systematic. Consistent. And it worked. It’s almost foolproof.
Open that account today, set up automatic contributions, and commit to the decade-long journey. You’ll be a millionaire sooner than you think.
Disclaimer: This article is for educational purposes only and is not personalized financial advice. Investment returns are not guaranteed, and all investments carry risk of loss. Consider consulting with a fee-only financial planner for guidance specific to your individual financial situation.
