June 30, 2026·8 min read

The 4% rule, for people who don't retire in America

The 4% rule was measured on a 30-year US retirement funded in one currency. Retire early, retire abroad, or hold money across currencies and at least three of its assumptions stop holding. Here's where the safe withdrawal rate breaks, and what to use instead.

The 4% rule says you can retire once you’ve saved 25 times your annual expenses, then withdraw 4% of that pile in the first year and adjust for inflation each year after. It is the most useful single sentence in personal finance and the most quietly misapplied. It was measured on a 30-year US retirement, funded entirely by a US-dollar portfolio. Retire early, retire abroad, or hold money across currencies, and at least three of its assumptions stop holding. Here is where it breaks, and what to use instead.

Try the math: our free FIRE Number calculator lets you set your own withdrawal rate instead of assuming 4%, and shows the number that falls out in your currency. Override every assumption in it as you read.

Where the 4% rule actually comes from

The rule traces to two pieces of 1990s research: Bengen’s 1994 study and the Trinity study that followed. Both asked the same question of US market history: if you retired in any year since the 1920s and pulled an inflation-adjusted percentage of your starting portfolio for 30 years, what rate would have survived nearly every historical sequence? The answer that survived about 95% of them was 4%.

That is a genuinely good finding. But notice what it is: a backtest of a 30-year retirement, on US stocks and bonds, spending US dollars. The rule is only as valid as those three conditions. Every problem it has for people like us traces back to one of them.

Assumption 1: your retirement is 30 years long

FIRE breaks this one on day one. Retire at 45 and plan to live to 95 and your retirement is 50 years, not 30. A withdrawal rate that survived 95% of 30-year windows does not survive the same share of 50-year windows, because the longer the horizon, the more damage a bad first decade does.

This is sequence-of-returns risk: two retirees can earn the exact same average return over their retirement and end up in completely different places, purely because of the order the returns arrived in. A crash in year two, while you’re withdrawing, does far more harm than the same crash in year twenty.

Worked example. Two retirees, each starting with 10m NOK, each averaging 6% a year over 30 years, each withdrawing 4%. Retiree A gets a good first decade and a bad last one. Retiree B gets the same returns in reverse: a 30% drop in years two and three, while the withdrawals keep coming. Same average. Retiree A dies with money to spare. Retiree B runs the pile down to almost nothing by year 22. The average return told you nothing. The order told you everything.

For a 30-year horizon, 4% is defensible. For a 45-to-50-year early-retirement horizon, the research points closer to 3% to 3.5%. That is not a rounding difference. At 3.5% instead of 4%, your FIRE number is roughly 14% larger.

Assumption 2: one currency, start to finish

The 4% was measured in dollars, on dollar assets, funding dollar spending. If you spend in NOK or EUR but hold part of your portfolio in USD (or the reverse), your real withdrawal rate floats with the exchange rate whether you like it or not. Pull 4% in a year the krone strengthens 8% against your dollar holdings and you have really withdrawn closer to 4.3% of what you can actually spend at home.

The honest move is to pick the currency you will spend your retirement in, and measure your withdrawal rate in that currency, not the currency your assets happen to sit in. We wrote the longer version of this trap in Your savings rate is half FX; the same distortion that lies about your savings rate lies about your withdrawal rate.

Assumption 3: every krone is spendable

The rule assumes the whole pile is available to withdraw from on day one. For anyone with a pension, that is not true. Folketrygden, an occupational scheme, an IPS, a US 401(k): these count toward your net worth but you cannot live on them until an access age that is often decades after an early-retirement date.

So there are two numbers, not one. Accessible FI is the money you can actually draw from now. Total FI is everything, including the locked accounts that fill in later. The 4% rule applies to the accessible pile that has to carry you from your retirement date to your access age. Apply it to your total net worth and you will believe you can retire years before you actually can.

So what rate should you actually use?

The honest answer is that it is a band, not a constant, and it depends on things only you know:

30-year horizon, flexible spending: 4% is reasonable.
40-to-50-year early-retirement horizon: plan on 3% to 3.5%.
Willing to cut spending in bad years? Flexibility buys back rate. A retiree who can trim 10% in a downturn can safely start higher than one on a fixed budget.
Holding a cash buffer of one to two years’ expenses? This is the single biggest sequence-risk mitigation there is, because it means you are not forced to sell investments into a crash to eat.

Treat the rate as a starting hypothesis you stress-test against your own life, not a guarantee you retire on. That framing is the whole point.

The rate sets your number; how long it takes to reach that number is a separate question, driven mostly by your savings rate. We cover it in How long until you’re financially independent?.

How fjordFIRE handles this

fjordFIRE doesn’t hard-code 4%. You set your own safe withdrawal rate and the FIRE number recalculates from it live. Regional defaults start you somewhere sane (3.5% for a Norway profile) and you override anything. Real returns are Fisher-adjusted for your own inflation, in your own currency, so the number isn’t borrowing answers from a market that isn’t yours.

The Accessible FI vs Total FI split is built in, so the rule lands on the pile it’s actually meant for, and the Backstop pillar tracks your cash buffer in months of runway, the concrete version of the sequence-risk mitigation above.

What we don’t do: pretend a single number is a promise. We show a deterministic projection with every assumption visible and editable, not a thousand-run Monte Carlo cloud dressed up as certainty. The 4% rule is a frame for thinking clearly about your money. We’d rather show you the assumptions you can change than hide them behind one confident figure.

If you want to run your own number, the waitlist is open. Drop your email. Onboarding in small cohorts, no bank logins, no surveillance.

Go deeper: Lesson: The 4% Rule & Sequence Risk.

Companion tools: FIRE Number calculator · Coast FI calculator.