Rock County, Wisconsin, a core county of the Madison-Janesville-Beloit, WI market, holds $3.5B in deposits across 18 insured institutions and 34 branches. BMO Bank is the largest deposit holder at 15.1% share. The top three banks hold 43% of deposits, which places the county in the Fragmented band. Deposits have grown 12.4% since 2021 while the branch count rose by 3.0%. It produced $8.4B of real gross domestic product in 2024, ranking #407 of the 1,523 ranked counties by economic output.
Ranks show where the county stands among the 1,523 ranked counties (those within a Combined or Metropolitan Statistical Area that have a branch). They describe relative position, not a rating of market quality or suitability.
Deposit trend
Branches: 33 in 2021 to 34 in 2026. Institutions: 17 to 18. Top-three share: 47% to 43%.
Institutions by deposits
| Institution | Deposits | Share | 5‑yr deposits |
|---|---|---|---|
| BMO Bank | $522M | 15.1% | -4% |
| Johnson Bank | $495M | 14.3% | +13% |
| Bank First | $481M | 13.9% | +3% |
| Associated Bank | $376M | 10.9% | +9% |
| First Mid Bank & Trust | $359M | 10.4% | +4% |
| JPMorgan Chase Bank | $268M | 7.8% | +3% |
| Bank of Milton | $194M | 5.6% | +19% |
| Lake Ridge Bank | $150M | 4.3% | +75% |
| First Community Bank | $142M | 4.1% | +25% |
| The Bank of Brodhead | $100M | 2.9% | +81% |
| Old National Bank | $96M | 2.8% | +42% |
| Town Bank | $76M | 2.2% | +65% |
| U.S. Bank | $60M | 1.7% | +61% |
| Bank Cmg | $42M | 1.2% | +17% |
| CBI Bank & Trust | $39M | 1.1% | +33% |
| PremierBank | $28M | 0.8% | +62% |
| Farmers and Merchants Union Bank | $20M | 0.6% | +1% |
| Sauk Valley Bank & Trust Company | $6M | 0.2% | no 2021 presence |
The 18 insured institutions with a branch presence in this county, per the FDIC Summary of Deposits, June 30, 2026. Five-year change compares the same institution’s county deposits in 2021 and 2026. Institutions are tracked by FDIC certificate number, and where an institution acquired another bank, the acquired bank’s prior deposits are folded into the baseline so the change reflects the combined, continuing franchise rather than reading as new. “No 2021 presence” means neither the institution nor a bank it later absorbed reported deposits in this county that year. Deposit figures are nominal and are not adjusted for inflation.
Part of the Madison-Janesville-Beloit market
Rock County is one of 6 counties that make up the Madison-Janesville-Beloit, WI market, a Combined Statistical Area (ranked #56 of 293 U.S. markets by economic output). It produces 12.0% of the market’s output and holds 9.6% of its deposits.
| Measure | Rock County | Share of parent market |
|---|---|---|
| 2024 GDP | $8.4B | 12.0% |
| Deposits | $3.5B | 9.6% |
| Population | 166,472 | 17.7% |
View the full Madison-Janesville-Beloit market profile →
Recruiting in Rock County
Deposits are spread across a competitive field of institutions, so the bankers worth recruiting are dispersed across more of them. Who holds the deposits, and how contested the market is, shapes both the runway for growth and the competition you would be recruiting against. We recruit commercial relationship managers, banking teams, and market leaders for banks building in markets like Rock County.
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