Definition
The tendency for spending to rise automatically with income: each raise upgrades the car, the apartment, and the restaurants until the bigger paycheck saves no more than the old one did.
Why it matters
Creep is why high earners can have low net worth. It converts raises into permanent obligations instead of wealth, and it is invisible without tracking because no single upgrade feels expensive.
Example
After a $10,000 raise (about $580 a month after tax), a renter upgrades apartments (+$350) and adds a car payment (+$230). The savings rate is unchanged. Banking even half of every raise beats that outcome permanently.
Put it into practice
Related terms
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