Short version: 325 banks are headquartered in Illinois, holding $774.18 billion in total assets between them as of June 30, 2026. The median one holds $278M. The median Illinois bank earned 1.15% on its assets against 1.23% for the median US bank, on a margin of 3.67% against 3.83%.
How many banks are headquartered in Illinois?
325 banks filed an FFIEC call report for the quarter ending June 30, 2026 with a head office in Illinois. Between them they reported $774.18 billion in total assets. That is a count of charters headquartered there, which is not the same as a count of banks operating there: a bank chartered in a neighboring state with branches across this one is counted in the state its head office sits in, and its whole balance sheet goes with it.
Non-insured non-deposit trust companies are left out of every figure on this page. They hold a charter and file a report, but they take no deposits and make no loans, so a funding cost or a margin computed for one of them is a ratio over an empty denominator. The same exclusion is applied to the national medians, so the two columns below are measured on the same basis.
Illinois bank benchmarks against the national median
Each figure is the median across banks headquartered in Illinois, beside the median across every bank in the country that filed for the same quarter. The gap is in percentage points.
| Metric | Illinois | US median | Gap | |
|---|---|---|---|---|
| Return on assetsNet income as a share of average assets. The summary number. | 1.15% | 1.23% | −0.08 pp | In line |
| Net interest marginNet interest income over average earning assets: the spread business. | 3.67% | 3.83% | −0.16 pp | Worse than the US median |
| Efficiency ratioNoninterest expense per dollar of revenue. Lower is leaner. | 63.04% | 61.81% | +1.23 pp | In line |
| Cost of fundsInterest expense over interest-bearing liabilities: what the money costs. | 2.07% | 2.34% | −0.27 pp | Better than the US median |
| Loans to depositsHow much of the deposit base is lent out rather than held in securities. | 74.54% | 80.16% | −5.62 pp | Lower |
| Tier 1 leverage ratioTier 1 capital over average assets, with no risk weights applied. | 10.93% | 10.96% | −0.03 pp | In line |
Source: FFIEC call reports for the quarter ending June 30, 2026. Illinois medians are computed across all 325 banks headquartered there, at every size. National medians are computed across every filing bank, matching the figures published in the BankingLens benchmark articles for the same quarter.
What the numbers say
The median bank in Illinois pays 27 basis points less for its money than the median US bank, 2.07% against 2.34%, and earns 16 basis points less on the spread, 3.67% against 3.83%. Cheap funding that does not turn into margin points at the asset side rather than deposit pricing - a securities-heavy balance sheet, or a loan book at lower yields than the national mix.
On the expense side it runs an efficiency ratio of 63.04, level with the national 61.81, with return on assets at 1.15%, level with the country.
The median Illinois bank lends out 74.54% of its deposits against 80.16% nationally, so more of what it takes in sits in securities rather than loans, and carries tier 1 leverage capital of 10.93%, level with the country. Neither of those has a good direction on its own. A high loan-to-deposit ratio means a bank is putting its funding to work, and also that it has less room left before it has to buy more; capital beyond what a bank needs to absorb its own losses earns very little.
Banking in Illinois is concentrated. The largest charter headquartered there, BMO Bank of Chicago, IL, holds 32.9% of the state's bank assets, and the five largest hold 68.2% between them. The median bank holds $278M.
The largest banks headquartered in Illinois
The 10 largest by total assets, of 325. 10 of them have a page here carrying the rest of the call report picture.
| # | Bank | City | Assets | ROA | NIM |
|---|---|---|---|---|---|
| 1 | BMO Bank | Chicago | $255.0B | 0.15% | 3.24% |
| 2 | The Northern Trust Company | Chicago | $178.6B | 1.46% | 1.63% |
| 3 | CIBC Bank USA | Chicago | $66.5B | 1.51% | 3.12% |
| 4 | Busey Bank | Champaign | $18.1B | 1.33% | 3.74% |
| 5 | Byline Bank | Chicago | $9.9B | 1.69% | 4.49% |
| 6 | Wintrust Bank | Chicago | $9.6B | 1.96% | 3.83% |
| 7 | Lake Forest Bank & Trust Company | Lake Forest | $9.3B | 1.97% | 3.31% |
| 8 | First Mid Bank & Trust | Mattoon | $9.1B | 1.19% | 3.90% |
| 9 | First American Bank | Elk Grove Village | $8.6B | 1.51% | 3.49% |
| 10 | Old Second National Bank | Aurora | $6.9B | 1.68% | 5.19% |
Methodology
- Universe. Every US bank that filed an FFIEC call report for the quarter ending June 30, 2026 with a head office in Illinois, at every asset size. There is no size floor: a median that excluded small banks would not describe the place.
- Exclusion. Non-insured non-deposit trust companies (FFIEC peer group 401) are left out of every statistic, here and in the national column. They take no deposits and make no loans, so their ratios have no meaning and a handful of them would move a small state's median a long way.
- Median floor. A local median is published only when at least 8 banks are headquartered there. Below that the median is one institution's number rather than a distribution, so it is withheld and the banks are listed individually instead.
- National median. Computed across every filing bank on the same basis, and checked against the figures the BankingLens benchmark articles publish for the same quarter, so the two can never disagree.
- Where assets are counted. At the charter's head office, as filed. A national bank headquartered in this state contributes its entire balance sheet to the state total regardless of where the deposits were gathered.
- Source. FFIEC Central Data Repository, joined to bank identity - name, city, state and RSSD id - from the same filing. Figures are as reported by each institution and are not adjusted or restated.
- Reproducibility. This page is generated by
_tools/seo/build_state_pages.mjsfrom the published dataset. It is not hand-maintained, and it carries no figure that was typed in.
Related reading
- What is a good ROA for a bank? - quartiles by asset band, and how to read one quarter against four.
- What is a good net interest margin? - the formula, and how the margin moves through a rate cycle.
- What is a good efficiency ratio? - what actually moves the expense line, and what only looks like it does.
- What is a good cost of funds? - the funding half of the margin, and the half a bank can manage.
- What is a good loan to deposit ratio? - what the deposits are being used for once they arrive.
- What is a good tier 1 leverage ratio? - thresholds, the CBLR election, and quartiles by asset band.
- How to build a bank peer group - why a state is a market and a peer group is a comparison, and why you need both.
- Bank benchmarks for every state - the same tables for the other 50 jurisdictions.