I'm considering a job offer in a different city, and I'm trying to get a realistic picture of expenses. I found a cost of living index by city 2025, but the numbers seem off—it lists housing as only slightly more expensive than where I live now, but every apartment listing I see is almost double. How accurate are these indexes for actual budgeting?
Cost of living indexes are useful for rough city to city comparisons but they are not precise for budgeting. Housing tends to drive the numbers and a given apartment listing can be far higher than the city average.
A practical approach is to pull current rent for the exact neighborhoods you would live in and compare those monthly costs to the housing line in the index.
Also watch for data lag and sample bias since indexes blend many sources over different time frames.
In a market with rapid rent growth the index may look underpriced even though you are seeing high listings.
Make a personal budget by listing rent utilities groceries transit and insurance and then see how the result lines up with the city level index and adjust.
If you want I can help you sanity check a specific city and walk through the numbers you are seeing.