Old Second Bancorp (OSBC) is back in focus after board member Dennis Klaeser resigned on June 5, 2026, and the company chose to reduce its board size instead of immediately filling the vacancy.

The recent board change comes as Old Second Bancorp’s share price sits at $22.01, with a 30-day share price return of 7.73% and year to date gain of 12.99%. The 1-year total shareholder return of 33.28% and 3-year total shareholder return of 64.43% point to momentum that has been building rather than fading.

If this kind of steady banking story has your attention, it can be useful to see what else is driving investors’ interest in community and regional lenders through 20 top founder-led companies

With Old Second Bancorp reporting steady revenue and net income growth and trading only modestly below a US$23.20 analyst target while sitting on a sizable estimated intrinsic discount, is the stock offering real value, or is the market already pricing in future growth?

Most Popular Narrative: 5.1% Undervalued

Old Second Bancorp’s most followed valuation narrative pegs fair value at $23.20, a touch above the recent $22.01 close, which naturally raises questions about what is baked into those assumptions.

The recent Evergreen Bank acquisition is performing ahead of expectations, providing higher-than-expected profitability and a more favorable asset mix, which is expected to drive incremental revenue growth, strengthen net interest margin, and enhance ROA as integration is completed.

Curious what kind of revenue path, margin lift, and future earnings multiple are needed to justify that fair value tag on Old Second Bancorp stock? The narrative leans on steady top line expansion, higher profitability, and a lower future P/E than many investors might assume, all supported by a specific discount rate and planned share count changes.

Result: Fair Value of $23.20 (UNDERVALUED)

However, Old Second Bancorp’s heavy Illinois concentration and exposure to commercial real estate credit trends still have the potential to challenge that 5.1% undervalued narrative.

Another View On Old Second Bancorp’s Valuation

The fair value story for Old Second Bancorp does not stop at the $23.20 narrative. On pure earnings terms, the stock trades on a 13.2x P/E, slightly above its own fair ratio of 12.8x and the US Banks industry at 11.9x, which suggests investors are paying a small premium. Is that premium comfort, or added risk?

For a closer look at how that earnings multiple stacks up against the fair ratio and peers, and what it could mean for future repricing, take a look at the See what the numbers say about this price — find out in our valuation breakdown.

Next Steps

If this mixed picture on Old Second Bancorp has you weighing both upside and downside, it is worth moving quickly to review the full balance of potential 3 key rewards and 2 important warning signs

Looking for more investment ideas beyond Old Second Bancorp?

Do not stop with Old Second Bancorp. Broaden your watchlist with focused stock ideas built from hard numbers so you are not leaving potential opportunities on the table.

• Target resilience first by checking companies screened for stronger balance sheets and fundamentals through the solid balance sheet and fundamentals stocks screener (48 results)
• Hunt for pricing gaps where quality and value intersect by reviewing the 47 high quality undervalued stocks
• Build a more stable income stream by scanning for higher yielding opportunities using the 9 dividend fortresses

This article by Simply Wall St is general in nature. We provide commentary based on historical data and analyst forecasts only using an unbiased methodology and our articles are not intended to be financial advice. It does not constitute a recommendation to buy or sell any stock, and does not take account of your objectives, or your financial situation. We aim to bring you long-term focused analysis driven by fundamental data. Note that our analysis may not factor in the latest price-sensitive company announcements or qualitative material. Simply Wall St has no position in any stocks mentioned.