Securing both financial success and career opportunities comes at a cost — one that is growing each year. Overall, Americans need an average post-tax income of $68,499 to live comfortably in the U.S., according to recent data from SmartAsset. 

SmartAsset's study analyzed the after-tax income needed to live in the nation's 25 largest metro areas comfortably. To determine the required salary for a single individual with no kids in each city, SmartAsset employed the 50/30/20 rule, which defines a comfortable lifestyle as one in which 50% of after-tax income is applied to basic living expenses (needs), 30% to discretionary income (wants) and 20% to savings and debt.

The MIT Living Wage Calculator was used to calculate basic living expenses for each city. 

The post-tax salary needed in these 25 areas increased by around 20% throughout 2022, while inflation grew about 8%.

Persistent inflation has led Americans to think more consciously about the cost of living throughout the country, Susannah Snider, a certified financial planner and managing editor at SmartAsset, tells CNBC Make It. 

"Inflation is taking a bigger bite out of their paychecks and the cost of living is rising. What does it take in these cities to really feel not just like you're surviving financially, but like you're comfortable? Like you're thriving?" Snider says. 

How much Americans need to live comfortably

For the second year in a row, St. Louis is the most affordable city on the list, with a required after-tax salary of $57,446. In contrast, San Francisco requires the highest take-home pay to maintain a comfortable lifestyle at an after-tax salary of over $84,000.

Income demands in Southern California rose nearly 30% this year; the Riverside metro area, for example, had the most acute one-year increase in required income, up 27.28% from 2022. 

Here are the salaries needed to live comfortably in 15 major U.S. cities: 

1. San Francisco metro area: $84,026
2. San Diego metro area: $79,324
3. Boston metro area: $78,752
4. New York metro area: $78,524
5. Seattle metro area: $77,634
6. Los Angeles metro area: $76,710
7. Washington, D.C. metro area: $76,194
8. Miami metro area: $67,056
9. Atlanta metro area: $66,580
10. Phoenix metro area: $65,670
11. Chicago metro area: $65,500
12. Dallas metro area: $64,742
13. Houston metro area: $62,260
14. Philadelphia metro area: $61,678
15. St. Louis metro area: $57,446

Why does San Francisco top the list?

In cities like San Francisco, the cost of living comfortably exponentially increased over the past year, from roughly $74,000 in 2022 to about $84,000 in 2023, Snider says.

California cities' elevated cost of living can be explained, in part, by the state's high income, gas and sales taxes. In San Francisco, for example, residents face a statewide gas tax rate of $0.539 per gallon and a sales tax of 8.625%. 

San Francisco's $10,000 increase "really highlights just how much the rising cost of living might be making [residents] feel like maybe that salary last year, that allowed them to feel like they were living comfortably, isn't really going as far this year," Snider says.

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