Table of contents(7)
- 01Geo-arbitrage vs classic FIRE: up to 26 years off your FIRE timeline
- 02Quick refresher: the FIRE formula in 30 seconds
- 03The gap in two equations: classic FIRE vs geo FIRE
- 04Three classic corridors: Paris → Lisbon, Paris → Mexico, NYC → Bali
- 05The domino effect: why the year savings exceed the simple ratio
- 06⚠️ Three illusions to dispel before packing
- 07Key Takeaways
Geo-arbitrage vs classic FIRE: up to 26 years off your FIRE timeline
The previous module laid out the geo-arbitrage equation. Here we quantify its real impact on the two variables that matter: the FIRE Number (target capital) and Years to FI (time to independence). A well-chosen relocation typically divides the FIRE Number by 1.5x to 2.5x. And the years to FIRE by 2x to 3x. It's mechanical, not magical. Two canonical formulas are enough to prove it.
Quick refresher: the FIRE formula in 30 seconds
Two numbers define your entire FIRE plan. The FIRE Number = annual expenses × 25 (equivalent to a 4% safe withdrawal). Years to FI = the number of years before you get there, a function of your savings rate and real return. Baseline case: $36,000/year in expenses, 25% savings rate, 5% real return. Result: FIRE Number $900,000, Years to FI roughly 32 years. The full formula for years, ln(1 + r·M·(1−s)/s) / ln(1+r), only matters for understanding why geo-arbitrage hits both variables so hard at once. That's what we look at next.
The gap in two equations: classic FIRE vs geo FIRE
Three classic corridors: Paris → Lisbon, Paris → Mexico, NYC → Bali
🇫🇷→🇵🇹 Paris → Lisbon. Paris at $3,000/mo, Lisbon at $1,700/mo, income maintained at $4,200. Classic FIRE = $900,000, geo FIRE = $510,000. Ratio ÷ 1.76. Years to FI: 32 years to 14 years. That's 18 years saved. 🇫🇷→🇲🇽 Paris → Mexico City. Mexico at $1,200/mo. Classic FIRE = $900,000, geo FIRE = $360,000. Ratio ÷ 2.5. Years to FI: 32 years to 9 years. That's 23 years saved. 🇺🇸→🇮🇩 NYC → Bali. NYC equivalent to $4,500/mo, Bali at $1,000/mo, income $6,000. Classic FIRE = $1,350,000, geo FIRE = $300,000. Ratio ÷ 4.5. Years to FI: 33 years to 7 years. That's 26 years saved. The leverage turns massive when you keep your income and divide your cost by more than 3.
The domino effect: why the year savings exceed the simple ratio
Without geo-arbitrage, at a 25% savings rate and 5% real, you take about 32 years. With geo-arbitrage at 60% savings on a halved FIRE Number, you take about 12 years. Naively, you'd expect 32 / 2 = 16 years. Why 12? Because the Years-to-FI formula is non-linear in s: the (1−s)/s term explodes when s drops but collapses when s climbs. The higher your savings rate, the more dramatically each extra savings point shortens the years (the 'shockingly simple math' effect from Mr. Money Mustache). Geo-arbitrage activates this non-linearity.
⚠️ Three illusions to dispel before packing
(1) International lifestyle creep: a $360,000 FIRE Number in Mexico is valid only as long as you stay at $1,200/mo. If you adopt high-end expat standards ($3,000/mo in upscale neighborhoods), your true FIRE Number reverts to around $900,000. Geo-arbitrage requires real spending discipline. Not a luxury relocation. (2) Return risk: if you move back home at 50 (family, health, fatigue), your $360,000 capital only covers about $1,200/mo, around 40% of your home cost. Plan a buffer or a mixed FIRE Number ('Mexico-FI + return-FI'). (3) Exit tax: latent capital gains on tax-deferred accounts may become due upon expatriation (FR exit tax above €800K, US IRA restrictions). Anticipate with a tax specialist.
Key Takeaways
- 1Geo-arbitrage acts on both FIRE variables simultaneously. It divides the FIRE Number (proportional to cost) and shortens Years to FI (higher savings rate combined with a smaller FIRE Number).
- 2Three reference corridors: Paris→Lisbon (÷ 1.76 ; −18 years), Paris→Mexico (÷ 2.5 ; −23 years), NYC→Bali (÷ 4.5 ; −26 years).
- 3The year savings always exceed the simple cost ratio. The Years-to-FI formula is non-linear: each additional savings rate point dramatically shortens the trajectory.
- 4Three traps can wipe out the gain: international lifestyle creep, under-budgeted return to home country, exit tax (FR above €800K, US IRA restrictions). Build a mixed FIRE Number if a return is on the table.
Keep going
Frequently asked questions
FIRE Number = Annual expenses × 25. Since geo-arbitrage divides expenses (same lifestyle, lower cost of living), it mechanically divides the FIRE Number by the same ratio. Example: $36,000/year of expenses in Paris → FIRE Number $900,000. Same lifestyle in Lisbon (~$20,000/year) → FIRE Number $500,000. That's −$400,000 of target capital, at equal income.
Typical gain ranges from 10 to 26 years depending on the corridor. Paris → Lisbon: ~18 years (32 → 14). Paris → Mexico: ~23 years (32 → 9). NYC → Bali: ~26 years (33 → 7). The gain exceeds the simple cost ratio because Years to FI = ln(1 + r·M·(1−s)/s)/ln(1+r) is non-linear: a higher savings rate dramatically accelerates the trajectory, on top of a smaller FIRE Number to reach.
International lifestyle creep is trap #1. If you move to Mexico (local cost $1,200/mo) but adopt high-end expat standards ($3,000/mo in upscale neighborhoods, premium restaurants, international school), you cancel the cost gap and your true FIRE Number reverts to ~$900,000. Geo-arbitrage requires real spending discipline: relocation is a necessary, not sufficient, condition.
Yes, it's even recommended for profiles at risk of return (family, health, expat fatigue). If you accumulate $360,000 in Mexico but move back to Paris at 50, that capital only covers around $1,200/mo, about 40% of your Paris cost. Build a mixed target FIRE Number ('Mexico-FI $360K + return-buffer $200K', for example) or plan expatriation as a Coast phase (5-10 years to shorten the timeline, then return). Hybrid architectures are often more resilient than permanent all-geo.