What if the secret to retiring earlier isn't figuring out how to make millions of dollars, but figuring out how to live well on less?

 

That is the basic idea behind “LeanFIRE”, a variation of the Financial Independence, Retire Early (FIRE) movement that has been gaining attention in personal finance circles. The original idea is relatively simple: save and invest aggressively enough that you eventually have enough money to cover your living expenses without needing a traditional paycheck, as soon as possible. LeanFIRE takes that idea one step further by intentionally keeping those living expenses as low as reasonably possible.

 

 

Your spending determines your number

One of the most interesting parts of LeanFIRE is the math behind it. A commonly used FIRE guideline is the “Rule of 25.” You estimate how much you expect to spend each year in retirement and multiply that amount by 25. The result gives you a rough estimate of the investment portfolio you would need to support that level of spending.

For example:

• $30,000 of annual spending × 25 = $750,000
• $40,000 of annual spending × 25 = $1 million
• $60,000 of annual spending × 25 = $1.5 million

The Rule of 25 is based on the commonly discussed 4% withdrawal guideline, which suggests withdrawing approximately 4% of your portfolio in the first year of retirement and adjusting that dollar amount for inflation in subsequent years. The takeaway isn't that everyone needs exactly 25 times their expenses to retire. Remember, retirement is subjective! Everyone has different income in retirement and different savings. Rather, it demonstrates something important: the less you need to spend, the less money you need to accumulate. Gee, that almost makes too much sense.

 

 

Lean doesn't have to mean miserable

This is where LeanFIRE can get interesting. The goal isn't necessarily to deprive yourself of everything you enjoy. It's about being intentional about the difference between what you need and what actually makes you happy.

 

Maybe that means living in a smaller home, driving an older car, cooking more meals at home, limiting lifestyle inflation or being more selective about subscriptions and other recurring expenses. It might mean putting in a little extra effort (read: thought) to fighting off evil-mustache-twirling advertising agencies trying to get you to feel incomplete without trading them your money for their product.

 

It could also mean discovering that you don't actually need to retire completely.

 

Some people pursuing FIRE choose a version of the concept called BaristaFIRE, where investments cover a portion of their expenses while part-time or flexible work provides the rest. Others pursue CoastFIRE, where they save aggressively early in their careers and eventually reach a point where their existing investments can grow toward their retirement goal without additional contributions.

 

And that's one reason I think the FIRE movement is worth paying attention to even if you have absolutely no interest in retiring at 40.

 

 

Financial independence is the real goal

Imagine you don't need to leave your job tomorrow. But you know that if your company eliminated your position, you would have a substantial emergency fund, manageable expenses and investments working in the background. That's financial independence. Or maybe you reach a point where you can turn down a job that requires 60-hour weeks because you don't need the additional income badly enough to sacrifice your time. That's financial independence, too.

 

You may never want to live on a LeanFIRE budget permanently, but learning to keep your lifestyle from automatically expanding every time your income increases can have a powerful effect on your finances.

 

 

There is a catch

LeanFIRE isn't a magic formula, and it's not right for everyone. A retirement that begins decades before traditional retirement age could last 40 or 50 years. That means inflation, investment returns, healthcare costs, taxes, housing expenses and unexpected life changes all have a lot of time to affect your plan. The traditional 4% rule was designed around a 30-year retirement horizon, so someone planning for a much longer retirement needs to be more cautious about treating it as a guarantee.

 

There's also the question of how much frugality is too much. Saving aggressively for the future is admirable, but life is happening right now, too. If your financial plan requires you to skip every vacation, never eat at a restaurant or stress over every $5 purchase, you may eventually decide the trade-off isn't worth it. The best financial plan isn't necessarily the one that gets you to retirement the fastest. It's the one that helps you build the life you actually want.

 

 

So, what's your FIRE number?

You don't have to join the LeanFIRE movement to borrow one of its best ideas: your spending is one of the most powerful levers you have when planning for financial independence.

Take a look at what you spend in an average year. Then ask yourself: If I had to, what could I comfortably live without? And what would I never want to give up?

 

Understanding that difference can help you build a retirement plan that isn't just about accumulating the biggest possible number. It's about figuring out what financial freedom actually looks like for you.

 

Happy contemplating!

Chandler