Old Second National Bank
Aurora, IL
IDRSSD: 936136
Total Assets
$6.90B
Latest filing
Total Deposits
$5.66B
Latest filing
Net Interest Margin
5.26%
Profitability
Routing numbers
Primary routing transit numbers associated with this institution.
5 routesView all→
071001122AURORA, IL071900760AURORA, IL071916822AURORA, IL071923349AURORA, IL071925981AURORA, IL
Key People
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Locations
Main office and branches. Select to view on the map.
Main Office
Old Second National Bank
37 S River St
Aurora, IL 60506
Full Service - Brick and Mortar
Updated 01/30/2026Established 11/21/1887FDIC Certificate 2293
Branches (58)
Page 1 of 9| Name | Address | City / State |
|---|---|---|
| Old Second National Bank (Main) | 37 S River St | Aurora, IL |
| 9443 SOUTH ASHLAND AVENUE BRANCH | 9443 S Ashland Ave | Chicago, IL |
| FRANKFORT BRANCH | 20201 S La Grange Rd | Frankfort, IL |
| WSB VISA BUILDING LIMITED SERVICE BRANCH | 701 Westmore Meyers Rd | Lombard, IL |
| NORTH AURORA BRANCH | 200 John St | North Aurora, IL |
| FINLEY ROAD BRANCH | 2800 Finley Rd | Downers Grove, IL |
| CASS AVENUE BRANCH | 8001 Cass Ave | Darien, IL |
| STRATFORD SQUARE BRANCH | 355 W Army Trail Rd | Bloomingdale, IL |
Showing 7 of 58
Quarterly Trends
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Total Assets vs Total Liabilities
Loans & Leases vs Deposits
Interest Income vs Expense
Net Interest Income
Noninterest Expense vs Income
Net Income
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Institution Profile
| Institution Class | Commercial bank, national (federal) charter, Fed member, and supervised by the OCC |
| Primary Regulator | OCC |
| Established Date | 11/21/1887 |
| Community Bank | Yes |
| Ownership Type | Not Mutual |
| ZIP | 60506 |
| State and County Number | 17089 |
| Subchapter S Corporations | No |
| Trust Powers | Full Trust Powers Granted |
| Federal Reserve ID Number | 07 |
| Numeric code | 3 |
| Insured by FDIC | Institutions that are currently open and insured by the FDIC |
| Federal Reserve District | Chicago |
| Core Based Statistical Area Name | Chicago-Naperville-Elgin, IL-IN-WI |
Operational Info
| Number of Employees | 1,056 |
| Domestic Offices | 59 |
| Foreign Offices | 0 |
| US Offices | 0 |
| Directly owned by another bank (CERT) | No |
| Last Structure Change Effective Date | 07/01/2025 |
| Date of Deposit Insurance | 01/01/1934 |
| Primary Insurance Agency | DIF |
| Website | www.oldsecond.com |
| Data Updated | 01/30/2026 |
| CERT | 3603 |
| Office of The Comptroller District: | — |
| Office of Thrift Supervision Region | N/A |
Financial Summary
| Total Assets | $6.90B |
| Total Deposits | $5.66B |
| Total Liabilities | $5.99B |
| Total Equity Capital | $904.95M |
| Net Income | $31.18M |
| Net Loans and Leases | $5.18B |
| Assets Per Employee ($Millions) | $6.5M |
| Bank Premises and Fixed Assets | $94.94M |
| Cash and Balances due from Depository Institutions | $124.03M |
| Deposits Held in Domestic Offices | $5.66B |
Key Performance Ratios
| Return on Assets (ROA) | 1.8% |
| Return on Equity (ROE) | 13.78% |
| Net Interest Margin | 5.26% |
| Efficiency Ratio | 51.96% |
| Tier 1 Risk-Based Capital Ratio | 13.175% |
| Net Loans and Leases to Core Deposits | 0% |
| Credit Loss Provision to Assets | 0.17% |
| Cash Dividends to Net Income (YTD Only) | 0% |
| Equity Capital to Assets | 13.116% |
| Earning Assets to total Assets | 91.97% |
Income and Expense
| Total Interest Income | $102.29M |
| Total Noninterest Income | $12.88M |
| Total Interest Expense | $18.42M |
| Total Noninterest Expense | $51.51M |
| Net Interest Income | $83.87M |
| Pre-tax Net Operating Income | $42.24M |
| Provision for Credit Losses | $3.00M |
| Discontinued Operations (Extraordinary Gains - Net) | $0 |
Additional Financial Info
| Goodwill and Other Intangibles | $0 |
| All Other Assets | — |
| Other Real Estate Owned | $1.43M |
| Other borrowed funds | $229.82M |
| Federal Funds Sold & Reverse Repurchase Agreement | $0 |
| Federal Funds Purchased and Repurchased Agreement | $23.77M |
| All Other Liabilities | $79.77M |
| Total Liabilities and Capital | $6.90B |
Securities
| Securities | $1.09B |
| Available-for-sale debt securities | $1.09B |
| Equity securities with readily determinable fair values not held for trading | — |
| Held-to-maturity securities | $0 |
| Subordinated Debt | $0 |
| Trading Account Assets | $0 |
| Trading Liabilities | $0 |
Frequently Asked Questions
What are the total assets of Old Second National Bank?
$6.90B as of the latest filing.
How much are Old Second National Bank's total deposits?
$5.66B in total deposits.
Where is Old Second National Bank located?
Aurora, IL.
What is the Net Interest Margin?
5.26%.
How many domestic offices does it operate?
59.
When was it established?
11/21/1887.
What is the Return on Assets (ROA)?
1.8%.
How much are total loans and leases?
$5.18B (latest filing).
What is the total interest income (latest filing)?
$102.29M.