What separates millionaires from the average person struggling to get ahead financially?

It's not just luck, a high-paying job or an Ivy League degree. It's the way they think about money and the habits they consistently practice. The good news? These habits aren't exclusive to the wealthy. Anyone can use them to build wealth over time.

After becoming a millionaire at age 28 and spending over 16 years writing about personal finance, I've noticed four distinct habits that set self-made millionaires apart. These are the "get rich" habits that roughly 93% of Americans, who are not millionaires, overlook.

1. Consistently saving and investing

This is especially crucial today, with stock market volatility, inflation concerns, trade wars and recession fears causing hesitation among investors.

But here's the secret: Millionaires don't wait for the "perfect" time to invest. They know that time in the market beats trying to time the market. When the market drops, they see opportunity, not panic. They automate investments and treat downturns as chances to buy at a discount.

In contrast, the average American lets fear dictate their financial decisions — selling in downturns and hoarding cash instead of investing. This reactionary approach prevents them from building substantial wealth.

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I always aim to invest at least 20% of my income, and I increase that percentage as my earnings grow. Over time, compounding will work in my favor.

2. Building multiple streams of income

Relying on a single source of income, like your day job, is a risky move. In this day and age of automation, globalization and artificial intelligence, there's no such thing as job security.

The more income sources you have, the more financially secure you become. The average millionaire has multiple streams of income:

• Dividends from stocks
• Rental income from real estate
• Profits from side businesses
• Royalties from intellectual property
• Capital gains from stocks and private investments
• Interest from bonds or high-yield savings
• Freelance or consulting work

Multiple streams of income act as a financial safety net. If you lose your job, a rental property or dividend portfolio can keep cash flowing. If your business takes a hit, your investments provide a cushion. Diversification isn't just for your stock portfolio — it's for your entire financial life.

Look at ways you can generate extra income beyond your paycheck. Could you rent out a room in your home? Start a side hustle? Invest in assets that generate passive income? Give lessons in a skill or sport you are an expert in?

Millionaires don't just work for money — they make money work for them in multiple ways.

3. Thinking in terms of opportunity cost

Millionaires have the ability to think in terms of opportunity cost: what they're giving up in order to make a financial decision. This mindset shift is powerful because it helps them prioritize wealth-building activities over short-term gratification. With opportunity cost in mind, each dollar spent is thought out more thoroughly.

For example, instead of impulsively buying a new luxury car, a millionaire will ask: If I invest this $60,000 instead, what could it be worth in 10 years? If I invested the $60,000 in the S&P 500, at a 8% compound annual return, I could have $130,000 instead.

Instead of spending $5,000 on a vacation, they consider: Could this money be better used to acquire an asset that will generate returns to help take care of my retirement?

This doesn't mean they never spend money on nice things. They spend strategically, only after ensuring their core wealth-building goals are met.

Before making a major purchase, ask yourself:

• Will this increase in value over time?
• Will this improve my ability to earn more money?
• What am I sacrificing by spending this money today?

4. They have an unwavering belief that they deserve to be rich

While the three habits above are practical, there's one more habit that's just as important: self-belief. Millionaires don't see money as something reserved for a select few — they see it as something they can create and control.

The difference between someone who accumulates wealth and someone who doesn't often comes down to mindset. Do you believe you have what it takes to become a millionaire? Or do you assume wealth is out of reach? With millions of millionaires in the world, do you constantly ask yourself: Why not me as well?

The self-made millionaires I've met have a relentless drive. If they lose on an investment, they learn from their mistakes. They aren't afraid to ask for raises, start businesses or invest aggressively. They take action, take risks and put themselves in positions to succeed.

Sam Dogen is the founder of Financial Samurai and the author of "Millionaire Milestones: Simple Steps To Seven Figures," his latest book on building wealth in today's world. He also wrote the Wall Street Journal bestseller "Buy This, Not That." In 2012, Sam retired at 34 after working in investment banking for 13 years. He has been helping others achieve financial independence ever since.

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