State Cash Cost Index

What the Savings-Rate Gap Actually Costs, by State

Every state faces the same national gap between the best widely-available savings rate and the national average — what varies by state is how much survives after tax. On a realistic, income-matched balance, that's $683/year in Alaska (no state income tax) versus $104/year in Mississippi.

Last reviewed August 16, 2026 · SwitchWize Research Desk

Why this isn't just a bigger-number version of the national figure

Every household in the country is exposed to the same live rate spread. What changes by state is (1) which national income-percentile tier a state's median household lands in — which sets a realistic, Fed-sourced typical balance for that tier, not a flat guess — and (2) how much of the resulting gap survives that state's own top marginal tax rate on interest income. States with similar median income and no state income tax land on the exact same number; that's expected, not an error.

StateAnnual gap (after tax)Typical balance usedTop interest tax
Alaska (AK)$683$17,000None
New Hampshire (NH)$683$17,000None
Washington (WA)$683$17,000None
Colorado (CO)$653$17,0004.4%
Utah (UT)$651$17,0004.65%
Massachusetts (MA)$649$17,0005%
Maryland (MD)$644$17,0005.75%
Virginia (VA)$644$17,0005.75%
Connecticut (CT)$635$17,0006.99%
New Jersey (NJ)$610$17,00010.75%
Hawaii (HI)$608$17,00011%
California (CA)$592$17,00013.3%
Florida (FL)$289$7,200None
Nevada (NV)$289$7,200None
South Dakota (SD)$289$7,200None
Tennessee (TN)$289$7,200None
Texas (TX)$289$7,200None
Wyoming (WY)$289$7,200None
Arizona (AZ)$282$7,2002.5%
North Dakota (ND)$282$7,2002.5%
Indiana (IN)$280$7,2003.05%
Louisiana (LA)$280$7,2003%
Pennsylvania (PA)$280$7,2003.07%
Kentucky (KY)$277$7,2004%
Michigan (MI)$277$7,2004.25%
Ohio (OH)$277$7,2003.99%
Arkansas (AR)$276$7,2004.4%
North Carolina (NC)$276$7,2004.5%
Alabama (AL)$275$7,2005%
Illinois (IL)$275$7,2004.95%
Missouri (MO)$275$7,2004.8%
Oklahoma (OK)$275$7,2004.75%
West Virginia (WV)$274$7,2005.12%
Georgia (GA)$273$7,2005.49%
Iowa (IA)$273$7,2005.7%
Kansas (KS)$273$7,2005.7%
Idaho (ID)$272$7,2005.8%
Nebraska (NE)$272$7,2005.84%
New Mexico (NM)$272$7,2005.9%
Rhode Island (RI)$272$7,2005.99%
South Carolina (SC)$271$7,2006.4%
Delaware (DE)$270$7,2006.6%
Montana (MT)$269$7,2006.75%
Maine (ME)$268$7,2007.15%
Wisconsin (WI)$267$7,2007.65%
Vermont (VT)$264$7,2008.75%
Minnesota (MN)$261$7,2009.85%
Oregon (OR)$260$7,2009.9%
New York (NY)$257$7,20010.9%
Mississippi (MS)$104$2,7105%

Methodology

Primary ranking: each state's real Census median household income is matched to the nearest national income-percentile bracket from the Fed's 2022 Survey of Consumer Finances (recomputed by us from the Fed's own public microdata — see the "scf" source below), and that bracket's real median transaction-account balance ($7,200 for the middle bracket, for reference) stands in as the state's typical liquid balance. The live spread between SwitchWize's tracked best HYSA APY (4.4%) and the FDIC national-average savings APY (0.38%) is applied to that balance, then each state's own top marginal income-tax rate on interest is applied to get the after-tax annual dollar gap. States are ranked by this after-tax figure. A secondary, simpler table (flatBalanceRankAt25k, examples[]) repeats the same math on fixed $10k/$25k/$50k illustrative balances for readers who want round numbers instead.

The SCF-bracket balance is not a state measurement — the SCF does not publish liquid-asset data by state (only nationally, by income bracket; see scripts/generate-state-cash-cost-index.ts header for why). States with similar median income land in the same bracket and share the same balance figure; the resulting variation reflects real income differences, not measured regional saving behavior. The flat-balance examples are plainly hypothetical ($10k/$25k/$50k), not a claim about what any specific household holds. No state-level aggregate ("$X billion statewide") figure is published — see DELIBERATELY EXCLUDED in scripts/generate-state-cash-cost-index.ts for why.

Sources

How to cite this

SwitchWize. "State Cash Cost Index." Retrieved from https://www.switchwize.com/research/state-cash-cost-index.

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Educational information, not personalized financial advice. Rates are illustrative of current market conditions and should be confirmed with the provider.