LeanFIRE: A worthy goal for any man


I’ve been sharing FIRE and leanFIRE for years

FIRE meaning financial indepedencen, retire early….and it’s even more important today, in light of

  • COVID-19 that up-ended the entire world
  • Russian’s illegal invasion into Ukraine and terrorizing Europe and the world
  • China’s extended zero COVID policy (and not keen to bring in “western” vaccines)
  • the great resignation
  • how so many companies shrunk and terminated so many employees

If you have started your leanFIRE journey for at least 10+ years:

  1. you’d have an overall lowered and leaner lifestyle of lower expenses
  2. you’d have amassed an amount of cash-paying assets, be it dividend stocks, REITs, rental properties etc

which would help to make you a little more resilient towards these sudden world changes past couple of year.

Mathematical assumptions

Assuming you’d been living off $2K/month (so total $24K/year) and investing $2K/month (so also $24K/year) into dividend stocks.

Assuming the dividends are 6% per year, and you reinvest every single dividend dollar, by the end of 10 years, you’d have: $335,319.42

Your dividends of 6% of $335,319.42 from year 11 onwards will be $20,119.16. Divided by 12 months, that’d be $1,676.60 dividends a month.

That’s not bad, if you’re “only” spending $2K/month, because $1,676 is “only” 16% short.

Is 16% short okay, Nigel?

I take an optimistic approach, because frankly, you’d already have 84% of living expenses sorted out with your dividend income. The shortfall is around $330 bucks. A MONTH.

ANY part time job or side gigs can cover that short fall, because you’re very close to leanFIRE / coastFIRE.

So yes, 16% short isn’t too bad in my books.

So even if I lose my job, I know and am assured that 84% of my expenses are sorted, I just need a little part time work to cover that shortfall. If I still have a job, I’ll keep investing $2K/month and reinvesting the dividends for a good 3-5 years (up to a buffer of at least $3K/month in dividends).

How much is enough to retire (your leanFIRE or coastFIRE number)

CoastFIRE and leanFIRE are very different in nature, and I’ll cover them separately, and then you decide which camp you fall under.


This financial independence retire early approach takes a “leaner” way of lifestyle to save enough money and retire as soon as possible. Mostly, you will choose to live very, very minimally and save/invest the rest, and your retirement will be more frugal overall. This gets you to retire earlier than most (late 20s or 30s) BUT you trade-off with a smaller investment portfolio due to less time involved.

LeanFIRE approach may mean that the passive income from your portfolio may not allow you lavish lifestyle (so no expensive cars / holidays / spendings) ie retire earlier frugal lifestyle.

The average number to calculate leanFIRE is to take your annual expenses and multiply that by 25.

So if your monthly spend is $3000, then annually you spend $3000 x 12 = $36,000. 25x of this will be $900,000. Assuming you

  • save and invest $1,000 a month into 6% returns per year stable assets
  • reinvest that 6% every year

You can reach your target $900,000 in 28.5 years.

This is a common strategy for people who are wired to retire earlier and/or have overall lower spending expenses than  other households for example people who have no kids / single, senior citizens, living in tiny homes / vans etc.

LeanFIRE is generally about being willing to live simpler in retirement, and people who follow this approach usually try to live on less than $50,000 per year or lesser. They would be okay / willing to

  • move to a lower cost of living area
  • spend less on travel or experiences
  • cut back or simplify food and transport expenses


Financial independence, retiring early can be very tough for young people to save a large chunk of money upfront, especially when cost of living is higher now no matter where you go. LeanFIRE can take many, many years to achieve (even the example above is a good 28.5 years). CoastFIRE on the other hand, is another alternative.

The difference between coastFIRE and normal FIRE is that with normal, traditional fire, you have more than enough passive income from your passive income investments to cover your daily expenses. You’re “there”. CoastFIRE is more about the beginning or earlier journey of FIRE, and you focus on

Frontloading your coastFIRE number which will let you achieve FIRE in X years.

I gave an earlier coastFIRE example with Jake here.

The two top principles of coastFIRE are:

  1. you will still need to work to cover the basic living expenses BUT
  2. you no longer have to worry about saving money and investing for retirement

Because you frontload the coastFIRE investment amount as early as possible AND let compounded investment return work hard for you over a period of time (usually the time you choose to retire).

Example, say 25-year old Jane has saved $100,000 and wants to retire at 55. Assuming Jane doesn’t spend much, around $2,800 a month (total $33,600 per year) and Jane’s money grows at 6% per year, she will have $574,349.12 by 55. 6% of $574,349 is $34,460.94. Jane would have achieved her coastFIRE number at age 25.

If I’m 35 want coastFIRE and retire with $1 million at 65, and say I’ve $200,000 to invest. Assuming annual returns of 6%, with the 6% reinvested over 40 years, I would have achieved it

within 28 years, by then I’ll be 63 years old. 2 years early.

Thing about this coastFIRE approach is that I will still have to work to cover living expenses as my investment work its compounding over time, but I will be on point for retirement without needing to add any extra savings – this is what it means to

coast into retirement

Of course, knowing myself, I will want more buffer, so I will top up / add in additional monies over the years to grow the principle more, and this will lead to

  • shaving off the years to hit $1M but more importantly
  • I’d have a larger (and more defensive) amount above $1M for buffers

What I like about coastFIRE is that it takes a lot of mental stress away from the get-go, and I can choose to work simpler or less hours at my work, knowing and having confidence that I can retire at X amount and years which is working for me. This is the biggest benefit in my opinion. To add on to that, secondary benefits are less sacrifices upfront:

  • no longer have to be stressed by counting dollars for vacations or big spends or small spends
  • dont have to choosing higher yielding projects with a lot more stress or tolerate rubbish people at work
  • even if I lose my job, I can choose a simple low paying job to pay the daily expenses and I’ll “still be okay”

This allows me to enjoy the journey of life more.

CoastFIRE first then slowly work towards leanFIRE then FIRE

It’s true, this idea of financial independence, retire early can be such a big idea that we start to shut down cos we get overwhelmed right? Here’s how I do it.

I call it the eat-the-elephant-one-bite-a-time method.

The “normal” FIRE means that you have enough passive income from your passive income investments to cover all your living expenses, and it can take quite a chunk of money and time to get here; but for us who are just beginning, let me introduce you the idea of


Yeah, it was nice to find out that there’s different stages of financial independence retire early, which makes sense once you think about it. After all, no one “suddenly” becomes financially independent retire early right?

Lol, so true but I didnt think about it earlier?

So coastFIRE is basically an early stage milestone for financial independence retire early dudes (and dudettes). The goal at this point is so save very, very aggressively as early as possible so that you can invest aggressively such that the compound interest of your investment will carry you all the way towards retirement.

To break down coastFIRE is 3 steps:

  1. is saving to investi as much as possible as early as possible
  2. reinvest the compound interest over a period of time
  3. to achieve financial independence / retirement at a particular time

CoastFIRE calculation example

Say an example of person A, let’s call him Jake. Jake is 24 this year, and he wants the usual:

  • passive income
  • retire early

He calculates and finds that he “just” needs $72,000 a year to retire. In today’s number’s that’s actually decent, around $6,000 per month to spend. Working backwards, assuming a standard 6% return per year, $72,000 / 6% = $1,200,000.00. That’s a big chunk of change, but he knows that he has time on his side, which takes off stress.

Two approaches to coastFIRE

CoastFIRE math

Save like mad and find $279,590 and put into a stable investment that will provide 6% return on investment; and reinvest every year for 25 years.

What I really really like about this approach is that it FRONTLOADS everything: once off $279,590 and let the interest keep compounding and growing by itself. Jake will save like mad and earn as much as he can, then frontload the entire $279,590 ONCE OFF and then just leave it be.

The amount will compound and keep compounding and after 25 years, Jake would 49, and he would have $1.2M in his account.

Every year, he can draw out from the 6% which translates to about $72K/year. If he can draw out less, then more can be compounded for the next year.

During this 25 years, he of course must work to sustain his day to day, but he can look forward for a pay day in 25 years time with confidence. This method frontloads a lot, but at the same time, offloads financial strain from the early stage.

Jake can keep adding to this amount in the meantime to either shave off years needed to hit the coastFIRE amount, or have more than enough at the end of the 25 years.

Risks or downsides to coastFIRE and how to manage

  1. Risk of investment tanking. What if the % returns drop?
  2. What if he loses his job?
  3. Investor as the risk: what if he sells early due to something happening (medical, mental issue, fraud etc)

As you can see, coastFIRE is a very powerful long term stress reliever, but there are a few risk/weak points as I mention above. There are workarounds for these potential risks, as I write in orange.

  1. Risk of investment tanking. What if the % returns drop? Jake should buffer at least 20% in the total invested amount AND instead of fully withdrawing 6% yearly, to instead only draw 3-4% to allow compounding to account for inflation, market downturns and growth. Only invest in very stable asset classes such as global ETFs or index funds
  2. What if he loses his job? This isn’t the biggest issue in my opinion, especially after Jake has front loaded the entire coastFIRE amount needed to grow in X years. Even if he takes a basic job to survive or for less stress, the model will work.
  3. Investor as the risk: what if he sells early due to something happening (medical, mental issue, fraud etc). This is very advanced and much more complex stuff, and I have thought about it, The only workaround for this from my current understanding is to create a trust and place the entire amount with specific instruction and conditions into it. The biggest risk of any investor is himself, and it’s the investor’s responsibility to not only protect his investment from others but also from screwing it up himself. It costs money to create and maintain a trust fund, which will need to be paid from the returns of the investment, so this will need to be computed as well.