$120K in Lafayette = $122,824 in Idaho Falls
Your $120K salary in Lafayette (COL 85) has the same purchasing power as $122,824 in Idaho Falls (COL 87). Idaho Falls is more expensive — you'd need 2% more to maintain the same lifestyle.
Budget breakdown — $120K in both cities
What $120K actually buys you in each city after taxes and core expenses.
| Expense | Lafayette $120K | Idaho Falls $120K (same salary) |
|---|---|---|
| Monthly take-home | $6,725 | $6,575 |
| 1BR rent | $1,100 | $1,100 |
| Groceries | $361 | $365 |
| Transport | $42 | $35 |
| Utilities | $208 | $142 |
| Internet | $58 | $65 |
| Left after essentials | $4,956/month | $4,868/month |
Frequently asked questions
What is $120K in Lafayette equivalent to in Idaho Falls?
$120K in Lafayette (COL index 85) has the same purchasing power as $122,824 in Idaho Falls (COL index 87). That's 2% more than your current salary.
If I move from Lafayette to Idaho Falls keeping my $120K salary, will I be better off?
Not necessarily. Core expenses in Idaho Falls are higher, so on the same $120K salary you'd have $88 less per month. You'd need to earn $122,824 to maintain the same standard of living.
How is the salary equivalent calculated?
The equivalent salary is calculated by multiplying your current salary by the ratio of the two cities' overall cost of living indices: $120K × (87 ÷ 85) = $122,824. This adjusts for differences in housing, food, transport, and general cost of living.
Other salary amounts — Lafayette to Idaho Falls
Equivalency uses overall COL index ratio. Take-home uses simplified federal/state brackets. Zillow · BLS · Numbeo · Q1 2026 · For general guidance only