$40K in Idaho Falls = $36,782 in Topeka
Your $40K salary in Idaho Falls (COL 87) has the same purchasing power as $36,782 in Topeka (COL 80). Topeka is cheaper — your money goes 8% further there.
Budget breakdown — $40K in both cities
What $40K actually buys you in each city after taxes and core expenses.
| Expense | Idaho Falls $40K | Topeka $40K (same salary) |
|---|---|---|
| Monthly take-home | $2,535 | $2,538 |
| 1BR rent | $1,100 | $940 |
| Groceries | $365 | $350 |
| Transport | $35 | $40 |
| Utilities | $142 | $150 |
| Internet | $65 | $55 |
| Left after essentials | $828/month | $1,003/month |
Frequently asked questions
What is $40K in Idaho Falls equivalent to in Topeka?
$40K in Idaho Falls (COL index 87) has the same purchasing power as $36,782 in Topeka (COL index 80). That's 8% less than your current salary.
If I move from Idaho Falls to Topeka keeping my $40K salary, will I be better off?
Yes. If you keep earning $40K after moving to Topeka, you'd have $175 more per month after core expenses — because Topeka is cheaper than Idaho Falls.
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: $40K × (80 ÷ 87) = $36,782. This adjusts for differences in housing, food, transport, and general cost of living.
Other salary amounts — Idaho Falls to Topeka
Equivalency uses overall COL index ratio. Take-home uses simplified federal/state brackets. Zillow · BLS · Numbeo · Q1 2026 · For general guidance only