Basis of Presentation	6 Months Ended
Jun. 30, 2026
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation General In the opinion of management, the accompanying unaudited consolidated financial statements contain all adjustments necessary to present fairly the consolidated balance sheets, statements of income, comprehensive income (loss), changes in stockholders’ equity, and cash flows of Nicolet Bankshares, Inc. (the “Company” or “Nicolet”) and its subsidiaries, as of and for the periods presented, and all such adjustments are of a normal recurring nature. All material intercompany transactions and balances have been eliminated. The results of operations for the interim periods are not necessarily indicative of the results to be expected for the entire year. These interim consolidated financial statements have been prepared according to the rules and regulations of the Securities and Exchange Commission and, therefore, certain information and footnote disclosures normally presented in accordance with generally accepted accounting principles in the United States of America (“U.S. GAAP”) have been omitted or abbreviated. These consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements and footnotes included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2025. Segment Information The Company has determined that its current community bank operating model is structured whereby all banking locations serve a similar base of primarily commercial customers utilizing a company-wide offering of similar products and services managed through similar processes and technology platforms that are collectively reviewed by the Company’s Chief Executive Officer, who has been designated as the chief operating decision maker (“CODM”). The CODM regularly assesses performance of the aggregated single banking segment in determining how to allocate resources. The banking segment derives revenue from customers by providing a broad array of loan and deposit products to businesses, consumers and government municipalities. The CODM assesses performance of the banking segment and decides how to allocate resources based on net income as reported in the Company’s consolidated statements of income. The measure of segment assets is based on total assets as reported on the consolidated balance sheets. For the periods presented, there were no adjustments or reconciling items between the banking segment net income and consolidated net income as presented in the consolidated statements of income, and there were no adjustments or reconciling items between the banking segment total assets and total assets as presented on the consolidated balance sheets. Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect: the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities as of the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. These estimates are based on information available to management at the time the estimates are made. Actual results could differ from those estimates. Significant Accounting Policies Update All significant accounting policies followed in the preparation of the quarterly financial statements are disclosed in the Company’s Annual Report on Form 10-K for the year ended December 31, 2025. There have been no changes to these accounting policies during 2026 except as it relates to the accounting for the ACL-loans. During first quarter 2026, the Company transitioned from using a historical loss rate method to a discounted cash flow (“DCF”) method for estimating expected credit losses on segmented loan pools that exhibit similar risk characteristics. There was no change to the ACL methodology as it relates to PCD and other credit-deteriorated loans, which continue to be individually evaluated with a specific reserve established for the aggregate collateral or DCF shortfall. Under the DCF method, the Company generates cash flow projections at the instrument level wherein payment expectations are adjusted for estimated prepayment speed, curtailments, probability of default, and loss given default. The modeling of expected prepayment speeds and curtailment rates are based on historical internal data. The Company uses regression analysis of historical internal and peer data to determine which variables are best suited to be economic variables utilized when modeling lifetime probability of default and loss given default. This analysis also determines how expected probability of default and loss given default will react to forecasted levels of the economic variables, which may include the U.S. unemployment, national retail sales, CRE index, and U.S. gross domestic product. Under the DCF method, management has determined that four quarters represents a reasonable and supportable forecast period and then reverts back to the long-run average of each considered economic factor over a four quarter period. Management leverages economic projections from a reputable and independent third party to inform its loss driver forecasts over the four quarter forecast period. Other internal and external indicators of economic forecasts are also considered by management when developing the forecast metrics. The combination of adjustments for credit expectations (default and loss) and timing expectations (prepayment and curtailment) produces an expected cash flow stream at the instrument level. Instrument effective yield is calculated, net of the impacts of prepayment assumptions, and the instrument expected cash flows are then discounted at that effective yield to produce an instrument level net present value of expected cash flows (“NPV”). An ACL is established for the difference between the instrument’s NPV and amortized cost basis. In addition, management utilizes qualitative factors to adjust the calculated ACL as appropriate. Qualitative factors are based on management’s judgment of company, market, industry, or business specific data, changes in underlying loan composition of specific portfolios, changes in collateral values, and trends relating to credit quality, delinquency, nonaccrual, or adversely rated loans. The transition to the DCF methodology for pooled loan segments did not have a significant impact to the recorded ACL. Recent Accounting Pronouncements Adopted In November 2025, the FASB issued ASU 2025-08, Financial Instruments - Credit Losses (Topic 326): Purchased Loans. This ASU expands the scope of the “gross up” method, formerly applicable only to PCD loans, to include non-PCD loans that meet certain criteria, now referred to as “purchased seasoned loans” (“PSLs”). Under this model, an allowance for expected credit losses is recognized at acquisition, offsetting the loan’s amortized cost basis, thereby eliminating the day one credit loss expense previously required for non-PCD loans. PSLs are defined as non-PCD loans acquired (1) through a business combination, or (2) purchased more than 90 days after origination when the acquirer was not involved in the origination. The updated guidance is effective for annual reporting periods beginning after December 15, 2026, and interim reporting periods within those annual reporting periods, with early adoption permitted. The Company early adopted this standard for the acquisition completed in first quarter 2026, as discussed in Note 2. Future Accounting Pronouncements In September 2025, the FASB issued ASU 2025-06, Intangibles - Goodwill and Other - Internal-Use Software (Subtopic 350-40): Targeted Improvements to the Accounting for Internal-Use Software. The amendments in this ASU make targeted improvements in the guidance for the different methods of software development. Specifically, this update removes all references to prescriptive and sequential software development stages; rather, an entity is required to start capitalizing software costs when both of the following occur: management has authorized and committed to funding the software project, and it is probable that the project will be completed and the software will be used to perform the function intended. The updated guidance is effective for annual reporting periods beginning after December 15, 2027. In November 2024, the FASB issued ASU 2024-03, Income Statement - Reporting Comprehensive Income - Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses. The amendments in this ASU require disclosure in the notes to financial statements of specified information about certain expenses, such as employee compensation, depreciation, and intangible asset amortization. The updated guidance is effective for annual reporting periods beginning after December 15, 2026. Reclassifications Certain amounts in the 2025 consolidated financial statements have been reclassified to conform to the 2026 presentation. During first quarter 2026, Nicolet reclassified fully reciprocated deposit balances with ICS from brokered deposits to core deposits to be more consistent with the presentation typically used by peer banks. The ICS reciprocal deposits are part of the IntraFi Network Deposits program, which is used by financial institutions to distribute deposits that exceed FDIC insurance coverage limits to numerous institutions in order to provide insurance coverage for all participating deposits. Prior periods have been restated to reflect this change. There was no change to total deposits or the deposit categories.

In the opinion of management, the accompanying unaudited consolidated financial statements contain all adjustments necessary to present fairly the consolidated balance sheets, statements of income, comprehensive income (loss), changes in stockholders’ equity, and cash flows of Nicolet Bankshares, Inc. (the “Company” or “Nicolet”) and its subsidiaries, as of and for the periods presented, and all such adjustments are of a normal recurring nature. All material intercompany transactions and balances have been eliminated. The results of operations for the interim periods are not necessarily indicative of the results to be expected for the entire year.

These interim consolidated financial statements have been prepared according to the rules and regulations of the Securities and Exchange Commission and, therefore, certain information and footnote disclosures normally presented in accordance with generally accepted accounting principles in the United States of America (“U.S. GAAP”) have been omitted or abbreviated. These consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements and footnotes included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2025.

The Company has determined that its current community bank operating model is structured whereby all banking locations serve a similar base of primarily commercial customers utilizing a company-wide offering of similar products and services managed through similar processes and technology platforms that are collectively reviewed by the Company’s Chief Executive Officer, who has been designated as the chief operating decision maker (“CODM”). The CODM regularly assesses performance of the aggregated single banking segment in determining how to allocate resources.

The banking segment derives revenue from customers by providing a broad array of loan and deposit products to businesses, consumers and government municipalities. The CODM assesses performance of the banking segment and decides how to allocate resources based on net income as reported in the Company’s consolidated statements of income. The measure of segment assets is based on total assets as reported on the consolidated balance sheets. For the periods presented, there were no adjustments or reconciling items between the banking segment net income and consolidated net income as presented in the consolidated statements of income, and there were no adjustments or reconciling items between the banking segment total assets and total assets as presented on the consolidated balance sheets.

The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect: the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities as of the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. These estimates are based on information available to management at the time the estimates are made. Actual results could differ from those estimates.

All significant accounting policies followed in the preparation of the quarterly financial statements are disclosed in the Company’s Annual Report on Form 10-K for the year ended December 31, 2025. There have been no changes to these accounting policies during 2026 except as it relates to the accounting for the ACL-loans. During first quarter 2026, the Company transitioned from using a historical loss rate method to a discounted cash flow (“DCF”) method for estimating expected credit losses on segmented loan pools that exhibit similar risk characteristics. There was no change to the ACL methodology as it relates to PCD and other credit-deteriorated loans, which continue to be individually evaluated with a specific reserve established for the aggregate collateral or DCF shortfall.

Under the DCF method, the Company generates cash flow projections at the instrument level wherein payment expectations are adjusted for estimated prepayment speed, curtailments, probability of default, and loss given default. The modeling of expected prepayment speeds and curtailment rates are based on historical internal data. The Company uses regression analysis of historical internal and peer data to determine which variables are best suited to be economic variables utilized when modeling lifetime probability of default and loss given default. This analysis also determines how expected probability of default and loss given default will react to forecasted levels of the economic variables, which may include the U.S. unemployment, national retail sales, CRE index, and U.S. gross domestic product.

Under the DCF method, management has determined that four quarters represents a reasonable and supportable forecast period and then reverts back to the long-run average of each considered economic factor over a four quarter period. Management leverages economic projections from a reputable and independent third party to inform its loss driver forecasts over the four quarter forecast period. Other internal and external indicators of economic forecasts are also considered by management when developing the forecast metrics.

The combination of adjustments for credit expectations (default and loss) and timing expectations (prepayment and curtailment) produces an expected cash flow stream at the instrument level. Instrument effective yield is calculated, net of the impacts of prepayment assumptions, and the instrument expected cash flows are then discounted at that effective yield to produce an instrument level net present value of expected cash flows (“NPV”). An ACL is established for the difference between the instrument’s NPV and amortized cost basis. In addition, management utilizes qualitative factors to adjust the calculated ACL as appropriate. Qualitative factors are based on management’s judgment of company, market, industry, or business specific data, changes in underlying loan composition of specific portfolios, changes in collateral values, and trends relating to credit quality, delinquency, nonaccrual, or adversely rated loans. The transition to the DCF methodology for pooled loan segments did not have a significant impact to the recorded ACL.

In November 2025, the FASB issued ASU 2025-08, Financial Instruments - Credit Losses (Topic 326): Purchased Loans. This ASU expands the scope of the “gross up” method, formerly applicable only to PCD loans, to include non-PCD loans that meet certain criteria, now referred to as “purchased seasoned loans” (“PSLs”). Under this model, an allowance for expected credit losses is recognized at acquisition, offsetting the loan’s amortized cost basis, thereby eliminating the day one credit loss expense previously required for non-PCD loans. PSLs are defined as non-PCD loans acquired (1) through a business combination, or (2) purchased more than 90 days after origination when the acquirer was not involved in the origination. The updated guidance is effective for annual reporting periods beginning after December 15, 2026, and interim reporting periods within those annual reporting periods, with early adoption permitted. The Company early adopted this standard for the acquisition completed in first quarter 2026, as discussed in Note 2.

In September 2025, the FASB issued ASU 2025-06, Intangibles - Goodwill and Other - Internal-Use Software (Subtopic 350-40): Targeted Improvements to the Accounting for Internal-Use Software. The amendments in this ASU make targeted improvements in the guidance for the different methods of software development. Specifically, this update removes all references to prescriptive and sequential software development stages; rather, an entity is required to start capitalizing software costs when both of the following occur: management has authorized and committed to funding the software project, and it is probable that the project will be completed and the software will be used to perform the function intended. The updated guidance is effective for annual reporting periods beginning after December 15, 2027.

In November 2024, the FASB issued ASU 2024-03, Income Statement - Reporting Comprehensive Income - Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses. The amendments in this ASU require disclosure in the notes to financial statements of specified information about certain expenses, such as employee compensation, depreciation, and intangible asset amortization. The updated guidance is effective for annual reporting periods beginning after December 15, 2026.

Certain amounts in the 2025 consolidated financial statements have been reclassified to conform to the 2026 presentation. During first quarter 2026, Nicolet reclassified fully reciprocated deposit balances with ICS from brokered deposits to core deposits to be more consistent with the presentation typically used by peer banks. The ICS reciprocal deposits are part of the IntraFi Network Deposits program, which is used by financial institutions to distribute deposits that exceed FDIC insurance coverage limits to numerous institutions in order to provide insurance coverage for all participating deposits. Prior periods have been restated to reflect this change. There was no change to total deposits or the deposit categories.