<?xml version="1.0" encoding="us-ascii"?><InstanceReport xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"><Version>2.4.0.8</Version><ReportLongName>101 - Disclosure - Interim Financial Statements</ReportLongName><DisplayLabelColumn>true</DisplayLabelColumn><ShowElementNames>false</ShowElementNames><RoundingOption /><HasEmbeddedReports>false</HasEmbeddedReports><Columns><Column FlagID="0"><Id>1</Id><IsAbstractGroupTitle>false</IsAbstractGroupTitle><LabelSeparator>

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</LabelSeparator><Level>1</Level><ElementName>us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract</ElementName><ElementPrefix>us-gaap_</ElementPrefix><IsBaseElement>true</IsBaseElement><BalanceType>na</BalanceType><PeriodType>duration</PeriodType><IsReportTitle>false</IsReportTitle><IsSegmentTitle>false</IsSegmentTitle><IsCalendarTitle>false</IsCalendarTitle><IsEquityPrevioslyReportedAsRow>false</IsEquityPrevioslyReportedAsRow><IsEquityAdjustmentRow>false</IsEquityAdjustmentRow><IsBeginningBalance>false</IsBeginningBalance><IsEndingBalance>false</IsEndingBalance><IsReverseSign>false</IsReverseSign><FootnoteIndexer /><Cells><Cell FlagID="0" ContextID="" UnitID=""><Id>1</Id><IsNumeric>false</IsNumeric><IsRatio>false</IsRatio><DisplayZeroAsNone>false</DisplayZeroAsNone><NumericAmount>0</NumericAmount><RoundedNumericAmount>0</RoundedNumericAmount><NonNumbericText /><FootnoteIndexer /><CurrencyCode /><CurrencySymbol /><IsIndependantCurrency>false</IsIndependantCurrency><ShowCurrencySymbol>false</ShowCurrencySymbol><DisplayDateInUSFormat>false</DisplayDateInUSFormat></Cell></Cells><ElementDataType>xbrli:stringItemType</ElementDataType><SimpleDataType>string</SimpleDataType><IsTotalLabel>false</IsTotalLabel><UnitID>0</UnitID><Label>Interim Financial Statements [Abstract]</Label></Row><Row FlagID="0"><Id>2</Id><IsAbstractGroupTitle>false</IsAbstractGroupTitle><LabelSeparator>

</LabelSeparator><Level>2</Level><ElementName>us-gaap_QuarterlyFinancialInformationTextBlock</ElementName><ElementPrefix>us-gaap_</ElementPrefix><IsBaseElement>true</IsBaseElement><BalanceType>na</BalanceType><PeriodType>duration</PeriodType><IsReportTitle>false</IsReportTitle><IsSegmentTitle>false</IsSegmentTitle><IsCalendarTitle>false</IsCalendarTitle><IsEquityPrevioslyReportedAsRow>false</IsEquityPrevioslyReportedAsRow><IsEquityAdjustmentRow>false</IsEquityAdjustmentRow><IsBeginningBalance>false</IsBeginningBalance><IsEndingBalance>false</IsEndingBalance><IsReverseSign>false</IsReverseSign><PreferredLabelRole>terseLabel</PreferredLabelRole><FootnoteIndexer /><Cells><Cell FlagID="0" ContextID="from-2013-01-01-to-2013-06-30.363.0.0.0.0.0.0.0" UnitID=""><Id>1</Id><IsNumeric>false</IsNumeric><IsRatio>false</IsRatio><DisplayZeroAsNone>false</DisplayZeroAsNone><NumericAmount>0</NumericAmount><RoundedNumericAmount>0</RoundedNumericAmount><NonNumbericText>&lt;!--DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd" --&gt;&lt;div&gt; &lt;div&gt;&lt;!--StartFragment--&gt; &lt;p style="FONT: 10pt Times New Roman, Times, Serif; MARGIN: 0pt 0px"&gt; &lt;strong&gt;1. Interim Financial Statements&lt;/strong&gt;&lt;/p&gt; &lt;p style="FONT: 10pt Times New Roman, Times, Serif; MARGIN: 0pt 0px"&gt; &lt;strong&gt;&amp;nbsp;&lt;/strong&gt;&lt;/p&gt; &lt;p style="FONT: 10pt Times New Roman, Times, Serif; MARGIN: 0pt 0px; TEXT-INDENT: 0.5in"&gt; The accompanying interim unaudited condensed consolidated financial statements have been prepared in accordance with generally accepted accounting principles for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by generally accepted accounting principles for complete financial statements. In our opinion, all adjustments (consisting of normal recurring accruals) considered necessary for a fair presentation have been included. Operating results for the three and six month period ended June 30, 2013, are not necessarily indicative of the results that may be expected for the year ending December 31, 2013. For further information, refer to the financial statements and footnotes thereto included in our Annual Report on Form 10-K for the fiscal year ended December 31, 2012.&lt;/p&gt; &lt;p style="FONT: 10pt Times New Roman, Times, Serif; MARGIN: 0pt 0px"&gt; &lt;strong&gt;&amp;nbsp;&lt;/strong&gt;&lt;/p&gt; &lt;p style="FONT: 10pt Times New Roman, Times, Serif; MARGIN: 0pt 0px; TEXT-INDENT: 0.5in"&gt; The accompanying condensed consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America which contemplate continuation of the Company as a going concern.&lt;/p&gt; &lt;p style="FONT: 10pt Times New Roman, Times, Serif; MARGIN: 0pt 0px; TEXT-INDENT: 0.5in"&gt; &amp;nbsp;&lt;/p&gt; &lt;p style="FONT: 10pt Times New Roman, Times, Serif; MARGIN: 0pt 0px; TEXT-INDENT: 0.5in"&gt; The Company has recently transitioned into production. The Company has recurring net losses from operations, an accumulated deficit of $168.9 million as of June 30, 2013, and is incurring higher operating expenses while ramping up and improving its production processes. In addition, the Company continues payment of its debt service requirements associated with existing debt facilities.&lt;/p&gt; &lt;p style="FONT: 10pt Times New Roman, Times, Serif; MARGIN: 0pt 0px; TEXT-INDENT: 0.5in"&gt; &amp;nbsp;&lt;/p&gt; &lt;p style="FONT: 10pt Times New Roman, Times, Serif; MARGIN: 0pt 0px; TEXT-INDENT: 0.5in"&gt; In March 2013, the Company raised $10 million in gross proceeds (approximately $9.7 million, net of issuance costs) through a public offering of 5,000,000 shares of our common stock at a price of $2.00 per share. Additionally, the Company cash settled approximately $3.7 million in debt obligations.&lt;/p&gt; &lt;p style="FONT: 10pt Times New Roman, Times, Serif; MARGIN: 0pt 0px; TEXT-INDENT: 0.5in"&gt; &amp;nbsp;&lt;/p&gt; &lt;p style="FONT: 10pt Times New Roman, Times, Serif; MARGIN: 0pt 0px; TEXT-INDENT: 0.5in"&gt; During the three and six months ended June 30, 2013, the Company shipped approximately 4,921 and 7,206 ounces of gold, respectively, resulting in recognized revenue of approximately $6.8 million and $10.5 million, respectively. During the three and six months ended June 30, 2013, the Company shipped 42,992 and 59,542 ounces of silver, respectively, resulting in sales of approximately $0.9 million and $1.4 million, respectively. The Company exceeded its targeted production rate of 400 ounces per week, averaging over 413 gold-equivalent ounces per week for the quarter ended June 30, 2013.&lt;/p&gt; &lt;p style="FONT: 10pt Times New Roman, Times, Serif; MARGIN: 0pt 0px; TEXT-INDENT: 0.5in"&gt; &amp;nbsp;&lt;/p&gt; &lt;p style="FONT: 10pt Times New Roman, Times, Serif; MARGIN: 0pt 0px"&gt; &lt;em&gt;Liquidity and Management Plans&lt;/em&gt;&lt;/p&gt; &lt;p style="FONT: 10pt Times New Roman, Times, Serif; MARGIN: 0pt 0px; TEXT-INDENT: 0.5in"&gt; &amp;nbsp;&lt;/p&gt; &lt;p style="FONT: 10pt Times New Roman, Times, Serif; MARGIN: 0pt 0px; TEXT-INDENT: 0.5in"&gt; The accompanying unaudited condensed consolidated financial statements have been prepared assuming the Company will continue as a going concern. The Company has incurred net operating losses and negative cash flows from operations every year since inception. At June 30, 2013, the Company has cash and cash equivalents of $2.4 million. The Company incurred an operating loss of $11.3 million and used cash flows in operations of $8.4 million for the six months ended June 30, 2013 (including the direct shipment of gold from current assets for the payment of $2.7 million of debt obligations). The Company continues its efforts to increase production, reduce costs and working capital needs, improve efficiencies, and maximize funds available for working capital. The Company&amp;#39;s current capital resources include cash and cash equivalents and other working capital resources, cash generated through operations, and existing financing arrangements. The Company&amp;#39;s current mine plan will require that the Company utilize existing financing arrangements or raise additional funds. The Company has financed its activities principally from the sale of equity securities and from debt financing. While the Company has been successful in the past in obtaining the necessary capital to support its operations, and has similar future plans to access various capital resources, including registered debt or equity financings from its existing shelf registration or other means, there is no assurance that the Company will be able to obtain additional equity capital or other financing.&lt;/p&gt; &lt;p style="FONT: 10pt Times New Roman, Times, Serif; MARGIN: 0pt 0px"&gt; &amp;nbsp;&lt;/p&gt; &lt;p style="FONT: 10pt Times New Roman, Times, Serif; MARGIN: 0pt 0px; TEXT-INDENT: 0.5in"&gt; Insufficient near-term financing or future production rates and gold prices below management&amp;#39;s expectations would adversely affect the Company&amp;#39;s results of operations, financial condition and cash flows, and could raise substantial doubt about the Company&amp;#39;s ability to continue as a going concern.&lt;/p&gt; &lt;p style="FONT: 10pt Times New Roman, Times, Serif; MARGIN: 0pt 0px; TEXT-INDENT: 0.5in"&gt; &amp;nbsp;&lt;/p&gt; &lt;p style="FONT: 10pt Times New Roman, Times, Serif; MARGIN: 0pt 0px"&gt; &lt;strong&gt;Use of Estimates&lt;/strong&gt;&lt;/p&gt; &lt;p style="FONT: 10pt Times New Roman, Times, Serif; MARGIN: 0pt 0px"&gt; &lt;strong&gt;&amp;nbsp;&lt;/strong&gt;&lt;/p&gt; &lt;p style="FONT: 10pt Times New Roman, Times, Serif; MARGIN: 0pt 0px; TEXT-INDENT: 0.5in"&gt; In preparing financial statements in conformity with generally accepted accounting principles, we are required to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the financial statements and revenues and expenditures during the reported periods. Actual results could differ materially from those estimates. Estimates may include those pertaining to valuation of inventories, stockpiles and mineralized material on leach pads, the estimated useful lives and valuation of plant and equipment, mineral rights, deferred tax assets, convertible preferred stock, derivative liabilities, reclamation liabilities, stock-based compensation and payments, and contingent liabilities&lt;font style="COLOR: black"&gt;.&lt;/font&gt;&lt;/p&gt; &lt;p style="FONT: 10pt Times New Roman, Times, Serif; MARGIN: 0pt 0px; TEXT-INDENT: 0.5in"&gt; &amp;nbsp;&lt;/p&gt; &lt;p style="FONT: 10pt Times New Roman, Times, Serif; MARGIN: 0pt 0px"&gt; &lt;strong&gt;Depreciation and Amortization Presentation&lt;/strong&gt;&lt;/p&gt; &lt;p style="FONT: 10pt Times New Roman, Times, Serif; MARGIN: 0pt 0px"&gt; &lt;strong&gt;&amp;nbsp;&lt;/strong&gt;&lt;/p&gt; &lt;p style="FONT: 10pt Times New Roman, Times, Serif; MARGIN: 0pt 0px; TEXT-INDENT: 0.5in"&gt; Upon commencement of production in late 2012, the Company classified depreciation, depletion, and amortization expenses related to revenue generating assets into costs applicable to mining revenue. Depreciation, depletion and amortization expenses that are not associated with revenue generating assets are allocated to reclamation and exploration expenses, general and administrative expenses and hospitality operating costs based on the function of the associated asset. Consequently, certain amounts in prior periods have been reclassified to conform to the current period presentation. In prior periods all depreciation and amortization expenses were recorded within a separate depreciation and amortization line item.&lt;/p&gt; &lt;p style="FONT: 10pt Times New Roman, Times, Serif; MARGIN: 0pt 0px; TEXT-INDENT: 0.5in"&gt; &amp;nbsp;&lt;/p&gt; &lt;p style="FONT: 10pt Times New Roman, Times, Serif; MARGIN: 0pt 0px; TEXT-INDENT: 0.5in"&gt; We believe this change in presentation provides increased transparency and improved comparability of our costs applicable to mining revenue and other operating expenses. These reclassifications, consisting of $408,360 and $589,013 of depreciation and amortization for the three and six months ended June 30, 2012, respectively; had no effect on our reported consolidated loss from operations, net loss or per share amounts.&lt;/p&gt; &lt;p style="FONT: 10pt Times New Roman, Times, Serif; MARGIN: 0pt 0px; TEXT-INDENT: 0.5in"&gt; &amp;nbsp;&lt;/p&gt; &lt;p style="FONT: 10pt Times New Roman, Times, Serif; MARGIN: 0pt 0px"&gt; &lt;strong&gt;Comprehensive Income&lt;/strong&gt;&lt;/p&gt; &lt;p style="FONT: 10pt Times New Roman, Times, Serif; MARGIN: 0pt 0px; TEXT-INDENT: 0.5in"&gt; &amp;nbsp;&lt;/p&gt; &lt;p style="FONT: 10pt Times New Roman, Times, Serif; MARGIN: 0pt 0px; TEXT-INDENT: 0.5in"&gt; There were no components of comprehensive loss other than net loss for the three and six months ended June 30, 2013 and 2012.&lt;/p&gt; &lt;p style="FONT: 10pt Times New Roman, Times, Serif; MARGIN: 0pt 0px; TEXT-INDENT: 0.5in"&gt; &amp;nbsp;&lt;/p&gt; &lt;p style="FONT: 10pt Times New Roman, Times, Serif; MARGIN: 0pt 0px"&gt; &lt;strong&gt;Recently Issued Accounting Pronouncements&lt;/strong&gt;&lt;/p&gt; &lt;p style="FONT: 10pt Times New Roman, Times, Serif; MARGIN: 0pt 0px"&gt; &lt;strong&gt;&amp;nbsp;&lt;/strong&gt;&lt;/p&gt; &lt;p style="FONT: 10pt Times New Roman, Times, Serif; MARGIN: 0pt 0px; TEXT-INDENT: 0.5in"&gt; There have been no recently issued accounting pronouncements through the date of this report that we believe will have a material impact on our financial position, results of operations, or cash flows.&lt;/p&gt; &lt;!--EndFragment--&gt;&lt;/div&gt; &lt;/div&gt;</NonNumbericText><FootnoteIndexer /><CurrencyCode /><CurrencySymbol /><IsIndependantCurrency>false</IsIndependantCurrency><ShowCurrencySymbol>false</ShowCurrencySymbol><DisplayDateInUSFormat>false</DisplayDateInUSFormat></Cell></Cells><ElementDataType>nonnum:textBlockItemType</ElementDataType><SimpleDataType>na</SimpleDataType><ElementDefenition>The entire disclosure for the quarterly financial data in the annual financial statements.  The disclosure may include a tabular presentation of financial information for each fiscal quarter for the current and previous year, including revenues, gross profit, income or loss before extraordinary items and earnings per share data. It also includes an indication if the information in the note is unaudited, comments on the aggregate effect of year-end adjustments, and an explanation of matters or transactions that affect comparability or are pertinent to an understanding of the information furnished.</ElementDefenition><ElementReferences>Reference 1: http://www.xbrl.org/2003/role/presentationRef

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