OSBC (Old Second Bancorp) Net Interest Margin (Bank Only) %: 5.65% (As of Mar. 2026)

Old Second Bancorp  (NAS:OSBC) Net Interest Margin (Bank Only) % Explanation

The negative value of Net Interest Margin (Bank Only) % mean the firm pays more interest for its debt than the interest revenue generated from its investment.

Old Second Bancorp Net Interest Margin (Bank Only) % Related Terms

The historical data trend for Old Second Bancorp's Net Interest Margin (Bank Only) % can be seen below:

* For Operating Data section: All numbers are indicated by the unit behind each term and all currency related amount are in USD.
* For other sections: All numbers are in millions except for per share data, ratio, and percentage. All currency related amount are indicated in the company's associated stock exchange currency.

Old Second Bancorp Net Interest Margin (Bank Only) % Chart

Old Second Bancorp Annual Data
	Trend	Dec16	Dec17	Dec18	Dec19	Dec20	Dec21	Dec22	Dec23	Dec24	Dec25
Net Interest Margin (Bank Only) %		Get a 7-Day Free Trial					2.65	4.11	5.06	5.09	5.64

Old Second Bancorp Quarterly Data
	Jun21	Sep21	Dec21	Mar22	Jun22	Sep22	Dec22	Mar23	Jun23	Sep23	Dec23	Mar24	Jun24	Sep24	Dec24	Mar25	Jun25	Sep25	Dec25	Mar26
Net Interest Margin (Bank Only) %	Get a 7-Day Free Trial															5.45	5.59	6.33	5.74	5.65

OSBC vs UVSP, CCB, MCB: Net Interest Margin (Bank Only) % Comparison

For the Banks - Regional subindustry, Old Second Bancorp's Net Interest Margin (Bank Only) %, along with its competitors' market caps and Net Interest Margin (Bank Only) % data, can be viewed below:

* Competitive companies are chosen from companies within the same industry, with headquarter located in same country, with closest market capitalization; x-axis shows the market cap, and y-axis shows the term value; the bigger the dot, the larger the market cap. Note that "N/A" values will not show up in the chart.

Old Second Bancorp Net Interest Margin (Bank Only) % vs Banks Industry

For the Banks industry and Financial Services sector, Old Second Bancorp's Net Interest Margin (Bank Only) % distribution charts can be found below:

* The bar in red indicates where Old Second Bancorp's Net Interest Margin (Bank Only) % falls into.

Old Second Bancorp Net Interest Margin (Bank Only) % Calculation

Net Interest Margin (Bank Only) % (NIM) is a measure of the difference between the interest income generated by banks or other financial institutions and the amount of interest paid out to their lenders (for example, deposits), relative to the amount of their interest-earning assets. It is usually calculated as a percentage of what the financial institution earns on loans in a time period and other assets minus the interest paid on borrowed funds divided by the average amount of the assets on which it earned income in that time period (the average earning assets).

Old Second Bancorp's annualized Net Interest Margin (Bank Only) % for the fiscal year that ended in Dec. 2025 is calculated as

where

Old Second Bancorp's annualized Net Interest Margin (Bank Only) % for the quarter that ended in Mar. 2026 is calculated as

where

* For Operating Data section: All numbers are indicated by the unit behind each term and all currency related amount are in USD.
* For other sections: All numbers are in millions except for per share data, ratio, and percentage. All currency related amount are indicated in the company's associated stock exchange currency.

Note: Interest Expense is the negative value.

In the calculation of annual Net Interest Margin (Bank Only) %, the Net Interest Income (for Banks) of the last fiscal year and the average earning assets over the fiscal year are used. In calculating the quarterly data, the Net Interest Income (for Banks) data used here is four times the quarterly (Mar. 2026) net interest income data. Net Interest Margin (Bank Only) % is displayed in the 30-year financial page for Banks.

Old Second Bancorp Business Description