RunMyWealth
Retire Abroad
Behaviour·4 min read·20 September 2026

Your Coffee Habit vs. An Index Fund: We Did the Math

We ran the numbers on the internet's favorite personal-finance cliché

Key takeaways

  • A $5/day habit is $150/month — redirected into an index fund at a 7% average return, that's roughly $183,000 after 30 years
  • The gap isn't really about coffee — it's about where the same dollars end up sitting
  • The math is identical for any $150/month habit, not just coffee — a subscription, takeout, anything recurring

Everyone's heard some version of "skip the coffee, retire rich." It's mostly used as a punchline. So we actually ran the number, instead of just repeating the meme.

The setup

A $5 daily coffee habit works out to about $150 a month. We compared two paths for that exact $150: spending it every month for 10, 20, and 30 years, versus investing it every month in a fund tracking the market's long-run historical average return, roughly 7% a year after inflation.

The scoreboard

10yr — spent
$18,000
10yr — invested
$25,970
20yr — spent
$36,000
20yr — invested
$78,150
30yr — spent
$54,000
30yr — invested
$183,000
The coffee was never really the problem. Not investing the difference was.

The catch nobody mentions

This only works if the money actually goes into an investment account — not just "not on coffee." Skipping the coffee and spending the $150 on literally anything else gets you to the exact same $0 as a lifetime of lattes. The habit was never coffee. It's what happens to the money afterward.

None of this means coffee is the enemy — it means the mechanism is bigger than the specific habit. Run your own number: your actual daily spend, your actual timeline, using the same calculator behind these figures.

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Educational information only. This article explains how a mechanism works. It isn't financial advice, a recommendation, or a plan tailored to your situation. Speak with a licensed professional before making any financial decision.

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