Under a traditional model, American workers were said to be able to rely on three sources of income to fund their lifestyle in retirement: pensions, Social Security and personal savings.

Over the past few decades, however, what experts once called the "three-legged stool" for retirees has gotten wobbly.

While many public sector workers still have access to a pension plan, private sector companies have all but eliminated them, shifting the burden onto employees to save in workplace-sponsored retirement plans. Just 15% of private industry workers had access to a pension in 2022, according to Bureau of Labor Statistics data.

Social Security is no sure thing either. The reserves used to pay beneficiaries are projected to become insolvent by 2035, at which point, without Congressional intervention, Uncle Sam will only be able to pay retirees 83% of their projected benefits.

To reach a comfortable retirement, then, you may have to reimagine what the model can look like, says Sam Dogen, an early retiree, founder of Financial Samurai and author of the upcoming book, "Millionaire Milestones."

"You're unlikely to be able to count on a pension. And you can't count on Social Security. If it's there — and it should be there — you can treat it as a bonus," he says. "You just have to count on yourself."

Dogen has done well betting on himself. In 2012, the now 47-year-old self-made millionaire was earning enough in passive and portfolio income to retire from his 9-to-5 at age 34. Dogen got there with what he calls a "new three-legged stool" — a model he says can work for those hoping to retire early as well as traditional retirees.

Leg 1: Tax-advantaged savings

A vestige from the traditional model, a tax-advantaged retirement account, such as a 401(k), is still an essential tool for retirement savers, Dogen says.

If you're in a workplace plan, such as a 401(k), you have the chance to earn "free money" in the form of matching contributions from your employer. Furthermore, you earn tax breaks — either when you deposit funds or withdraw them, depending on the type of account — for investing in such accounts.

And because 401(k)s and individual retirement accounts typically penalize you for withdrawing money before the age of 59½, you're incentivized to set aside money that can grow at a compounding rate until you're ready to retire.

It's smart to prioritize contributing as much as you can to such plans, Dogen says. "The first thing you should do is aim to max out your 401(k) and IRA or Roth IRA," he says. "Hopefully, it's something that becomes automatic, and you're not going to touch it until you're 59½."

For 2024, employees under the age of 50 can contribute up to $23,000 to a 401(k) and, provided they meet certain income requirements, up to $7,000 to an IRA.

Leg 2: Taxable investments

Once you're making steady contributions to accounts earmarked for retirement, you can begin building a portfolio of taxable investments, which might include a brokerage account or investments in real estate.

For Dogen, owning these sorts of investments was about accumulating as much wealth as possible: "Once it's a given that you're maxing out everything with tax-advantaged accounts, it's about building those taxable accounts as much as possible," he says.

Although you'll owe capital gains tax on any profit you earn from such investments, they also come with a degree of flexibility since the money isn't locked up until retirement. That means these investments can provide a stream of income in the form of stock dividends or rental income before you retire. That could contribute to an early retirement, if that's your goal, or it could lift some of the burden off your tax-advantaged accounts for providing retirement income.

If possible, Dogen says to contribute even more to these accounts than your maximum retirement contributions — an admittedly tall ask for many employees. But if you can, aim for this portion of your portfolio to double or triple your retirement accounts in value by the time you're 60 years old, he says.

Leg 3: X factor

While you may not be able to stash that kind of money away, virtually everyone can work on what Dogen calls an "X factor."

"You want to be working on something, either before or after work, that can eventually generate income," he says. "It can be a side hustle. Or everyone has a skill — you can teach that skill to other people."

Dogen taught tennis lessons in his youth, and started his website as a side project while working in investment banking.

The latter has not only provided supplemental income, but blossomed into more opportunities, Dogen says, including a pair of book deals. Plus, he says, "it's just fun."

For some people, this leg of the stool merely boils down to "work more" — not exactly an exciting proposition. But if done right, you may be able to hone a skill or expand on a hobby you love and, over time, have the option of turning it into a going concern.

Having that sort of flexibility is what will give you a true sense of financial security, says Dogen.

"Employment is not guaranteed," he says. Having another way to make money "not only gives you tremendous security, but also tremendous satisfaction. Because you're doing something you enjoy, you become an expert at it, and it's fulfilling."

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