Exhibit 99.3

Unaudited Pro Forma Condensed Combined Financial Statements

The unaudited pro forma condensed combined statements of income for the fiscal year ended December 31, 2014, and for the nine months ended September 30, 2015, combine the historical consolidated statements of operations of Centene and Health Net, giving effect to the merger and the transactions contemplated thereby as if they had occurred on January 1, 2014. The unaudited pro forma condensed combined balance sheet as of September 30, 2015, combines the historical consolidated balance sheets of Centene and Health Net, giving effect to the merger and the transactions contemplated thereby as if they had occurred on September 30, 2015. The historical consolidated financial information has been adjusted in the unaudited pro forma condensed combined financial statements to give effect to pro forma events that are (i) directly attributable to the merger and the transactions contemplated thereby, (ii) factually supportable, and (iii) with respect to the statements of income, expected to have a continuing impact on the combined results. The unaudited pro forma condensed combined financial information should be read in conjunction with the accompanying notes to the unaudited pro forma condensed combined financial statements. In addition, the unaudited pro forma condensed combined financial information was based on and should be read in conjunction with the following historical consolidated financial statements and accompanying notes:

The unaudited pro forma condensed combined financial information has been prepared by Centene using the acquisition method of accounting in accordance with GAAP. Centene has been treated as the acquirer in the merger for accounting purposes. The acquisition accounting is dependent upon certain valuation and other studies that have yet to commence or progress to a stage where there is sufficient information for a definitive measurement. The proposed merger has not yet received the necessary approvals from certain governmental authorities, and under certain relevant laws and regulations, before completion of the merger, there are certain limitations regarding what Centene can learn about Health Net. The assets and liabilities of Health Net have been measured based on various preliminary estimates using assumptions that Centene believes are reasonable based on information that is currently available. Differences between these preliminary estimates and the final acquisition accounting will occur, and those differences could have a material impact on the accompanying unaudited pro forma condensed combined financial statements and the combined company’s future results of operations and financial position. The pro forma adjustments are preliminary and have been made solely for the purpose of providing unaudited pro forma condensed combined financial statements prepared in accordance with the rules and regulations of the SEC.

Centene intends to commence the necessary valuation and other studies required to complete the acquisition accounting promptly upon completion of the merger and will finalize the acquisition accounting as soon as practicable within the required measurement period in accordance with ASC 805, but in no event later than one year following completion of the merger.

The unaudited pro forma condensed combined financial information has been presented for informational purposes only. The unaudited pro forma condensed combined financial information does not purport to represent the actual results of operations that Centene and Health Net would have achieved had the companies been combined during these periods and is not intended to project the future results of operations that the combined company may achieve after the merger. The unaudited pro forma condensed combined financial information does not reflect the realization of any cost savings following completion of the merger and also does not reflect any related restructuring and integration charges to achieve those cost savings.

Unaudited Pro Forma Condensed Combined Statement of Operations

For the Year Ended December 31, 2014

(In millions, except share data)

See the accompanying notes to the unaudited pro forma condensed combined financial statements, which are an integral part of these statements. The pro forma adjustments are explained in Note 6. Income Statement Pro Forma Adjustments.

Unaudited Pro Forma Condensed Combined Statement of Operations

For the Nine Months Ended September 30, 2015

(In millions, except share data)

See the accompanying notes to the unaudited pro forma condensed combined financial statements, which are an integral part of these statements. The pro forma adjustments are explained in Note 6. Income Statement Pro Forma Adjustments.

Unaudited Pro Forma Condensed Combined Balance Sheet

As of September 30, 2015

(In millions, except share data)

See the accompanying notes to the unaudited pro forma condensed combined financial statements, which are an integral part of these statements. The pro forma adjustments are explained in Note 7. Balance Sheet Pro Forma Adjustments.

NOTES TO THE UNAUDITED PRO FORMA CONDENSED

COMBINED FINANCIAL STATEMENTS

(IN MILLIONS, EXCEPT SHARE DATA)

1. Description of Transaction

On July 2, 2015, Centene, Chopin Merger Sub I, Inc. (“Merger Sub I”), Chopin Merger Sub II, Inc. (“Merger Sub II”) and Health Net entered into the merger agreement.

The merger agreement provides that, subject to the terms and conditions of the merger agreement, Merger Sub I will merge with and into Health Net, with Health Net continuing as the surviving entity and a direct wholly owned subsidiary of Centene. In addition, immediately following the completion of the merger and contingent upon Health Net’s receipt before the effective time of the merger of an opinion from Health Net’s outside legal counsel, that the mergers will constitute a reorganization under Section 368(a) of the Code, Health Net, as the surviving entity of the merger, will merge with and into Merger Sub II, with Merger Sub II surviving the subsequent merger as the surviving corporation.

In the merger, each share of Health Net common stock that is issued and outstanding immediately prior to the effective time of the merger (other than (i) any shares of Health Net common stock owned or held directly or indirectly by Centene, Health Net (including as treasury stock), Merger Sub I or Merger Sub II that will be cancelled upon completion of the merger, (ii) shares related to Health Net stock options, restricted stock units or performance share awards and (iii) any shares of Health Net common stock with respect to which appraisal rights are properly demanded and not withdrawn under the DGCL) will be converted into the right to receive $28.25 in cash and 0.622 of a validly issued, fully paid non-assessable share of Centene common stock. The exchange ratio will be adjusted appropriately to fully reflect the effect of any reclassification, stock split (including a reverse stock split), recapitalization, split-up, combination, exchange of shares, readjustment or other similar transaction (including any exercise of rights issued pursuant to the Health Net rights agreement), or any stock dividend declared thereon, with respect to the shares of either Centene common stock or Health Net common stock, with a record date prior to completion of the merger. No fractional shares of Centene common stock will be issued in connection with the merger. Instead of receiving any fractional shares, each holder of Health Net common stock will be paid an amount in cash, without interest, rounded down to the nearest cent, equal to the product of (x) the amount of the fractional share interest in a share of Centene common stock to which such holder would otherwise be entitled (rounded to three decimal places) and (y) the Centene stock value. Centene stockholders will continue to own their existing shares of common stock of Centene, which will not be changed by the transaction.

At the effective time of the merger, each option to purchase Health Net common stock that is outstanding and unexercised as of immediately prior to the effective time of the merger, whether or not then vested or exercisable, shall be cancelled in exchange for a cash payment of $28.25 for each share of Health Net common stock subject to the option, generally reduced by an amount of cash equal to any applicable withholding taxes, and 0.622 of a validly issued, fully paid and non-assessable share of Centene common stock for each share of Health Net common stock subject to the option, generally reduced by a number of shares of Centene common stock with a Centene stock value equal to the aggregate exercise price of the option.

At the effective time of the merger, each Health Net restricted stock unit and Health Net performance share award that is outstanding immediately prior to the effective time of the merger and either (i) is vested as of immediately prior to the effective time of the merger in accordance with the vesting schedule contained therein as in effect on the date of the merger agreement or (ii) becomes vested solely as a result of the consummation of the transactions contemplated by the merger agreement as a result of a non-discretionary vesting acceleration provision contained therein as of the date of the merger agreement shall be cancelled and automatically converted into the right to receive the merger consideration. Each other Health Net restricted stock unit or performance share award that is outstanding immediately prior to the effective time of the merger shall continue to have, and be subject to, the same terms and conditions (including the vesting schedule) as were applicable to such award immediately prior to the effective time of the merger, except that each such award will be adjusted based on an exchange ratio contained in the merger agreement and will thereafter relate to shares of Centene common stock rather than shares of Health Net common stock.

2. Basis of Presentation

The unaudited pro forma condensed combined financial information was prepared using the acquisition method of accounting and was based on the historical financial statements of Centene and Health Net. The acquisition method of accounting is based on ASC 805 and uses the fair value concepts defined in ASC 820, Fair Value Measurements.

ASC 805 requires, among other things, that most assets acquired and liabilities assumed be recognized at their fair values as of the acquisition date. In addition, ASC 805 requires that the consideration transferred be measured at the date the merger is completed at the then-current market price. This requirement will likely result in a per share equity component that is different from the amount assumed in these unaudited pro forma condensed combined financial statements.

ASC 820 defines the term “fair value” and sets forth the valuation requirements for any asset or liability measured at fair value, expands related disclosure requirements and specifies a hierarchy of valuation techniques based on the nature of the inputs used to develop the fair value measures. Fair value is defined in ASC 820 as “the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date.” This is an exit price concept for the valuation of the asset or liability. In addition, market participants are assumed to be buyers and sellers in the principal (or the most advantageous) market for the asset or liability. Fair value measurements for an asset assume the highest and best use by these market participants. As a result of these standards, Centene may be required to record the fair value of assets which are not intended to be used or sold and/or to value assets at fair value measures that do not reflect Centene’s intended use of those assets. Many of these fair value measurements can be highly subjective, and it is possible that other professionals, applying reasonable judgment to the same facts and circumstances, could develop and support a range of alternative estimated amounts.

Under the acquisition method of accounting, the assets acquired and liabilities assumed will be recorded, as of completion of the merger, primarily at their respective fair values and added to those of Centene. Financial statements and reported results of operations of Centene issued after completion of the merger will reflect these values, but will not be retroactively restated to reflect the historical financial position or results of operations of Health Net.

Under ASC 805, acquisition-related transaction costs (e.g., advisory, legal, accounting, valuation and other professional fees) are not included as a component of consideration transferred but are accounted for as expenses in the periods in which the costs are incurred. Total acquisition-related transaction costs expected to be incurred by Centene and Health Net are estimated to be approximately $115 million and $50 million, respectively, of which $18 million had been incurred as of September 30, 2015. Acquisition-related transaction costs expected to be incurred by Centene include estimated fees related to a bridge financing commitment agreement. Those costs are reflected in the unaudited pro forma condensed combined balance sheet as an increase to accrued expenses and other current liabilities, with the related tax benefits reflected as an increase in other current assets and the after tax impact presented as a decrease to retained earnings.

The unaudited pro forma condensed combined financial statements do not reflect the projected realization of cost savings following completion of the merger. These cost savings opportunities are from administrative cost savings, as well as network and medical management savings. Although Centene projects that cost synergies of approximately $75 million and $150 million will result in the first and second year following the merger, there can be no assurance that these cost synergies will be achieved. The unaudited pro forma condensed combined financial statements do not reflect projected pretax restructuring and integration charges associated with the projected cost savings, which are projected to be approximately $40 million to $50 million over a period of two years following completion of the merger. Such restructuring and integration charges will be expensed in the appropriate accounting periods after completion of the merger.

3. Accounting Policies

At completion of the merger, Centene will review Health Net’s accounting policies. As a result of that review, Centene may identify differences between the accounting policies of the two companies that, when conformed,

could have a material impact on the combined financial statements. At this time, Centene is not aware of any differences that would have a material impact on the combined financial statements. The unaudited pro forma condensed combined financial statements assume there are no material differences in accounting policies other than reclassifications detailed in Note 6.

4. Estimate of Consideration Expected to be Transferred

The following is a preliminary estimate of consideration expected to be transferred to effect the acquisition of Health Net:

Certain amounts may reflect rounding adjustments.

5. Estimate of Assets to be Acquired and Liabilities to be Assumed

The following is a preliminary estimate of the assets to be acquired and the liabilities to be assumed by Centene in the merger, reconciled to the estimate of total consideration expected to be transferred:

The fair value of identifiable intangible assets is determined primarily using variations of the “income approach,” which is based on the present value of the future after tax cash flows attributable to each identified intangible asset. Other valuation methods, including the market approach and cost approach, were also considered in estimating the fair value. Under the HSR Act and other relevant laws and regulations, there are significant limitations on Centene’s ability to obtain specific information about the Health Net intangible assets prior to completion of the merger.

At this time, Centene does not have sufficient information as to the amount, timing and risk of cash flows of all of Health Net’s identifiable intangible assets to determine their fair value. Some of the more significant assumptions inherent in the development of intangible asset values, from the perspective of a market participant, include: the amount and timing of projected future cash flows (including revenue and profitability); the discount rate selected to measure the risks inherent in the future cash flows; and the assessment of the asset’s life cycle and the competitive trends impacting the asset. However, for purposes of these unaudited pro forma condensed combined financial statements and using publicly available information, such as historical revenues, Health Net’s cost structure, industry information for comparable intangible assets and certain other high-level assumptions, the fair value of Health Net’s identifiable intangible assets and their weighted-average useful lives have been estimated as follows:

These preliminary estimates of fair value and weighted-average useful life will likely be different from the final acquisition accounting, and the difference could have a material impact on the accompanying unaudited pro forma condensed combined financial statements. Once Centene has full access to information about Health Net’s intangible assets, additional insight will be gained that could impact (i) the estimated total value assigned to intangible assets, (ii) the estimated allocation of value between finite-lived and indefinite-lived intangible assets and/or (iii) the estimated useful lives of intangible assets. The estimated intangible asset values and their useful lives could be impacted by a variety of factors that may become known to Centene only upon access to additional information and/or by changes in such factors that may occur prior to completion of the merger. These factors include, but are not limited to, changes in the regulatory, legislative, legal, technological and competitive environments. Increased knowledge about these and/or other elements could result in a change to the estimated fair value of the identifiable Health Net intangible assets and/or to the estimated weighted-average useful lives from what Centene has assumed in these unaudited pro forma condensed combined financial statements. The combined effect of any such changes could then also result in a significant increase or decrease to Centene’s estimate of associated amortization expense.

6. Income Statement Pro Forma Adjustments

This note should be read in conjunction with Note 1. Description of Transaction; Note 2. Basis of Presentation; Note 4. Estimate of Consideration Expected to be Transferred; and Note 5. Estimate of Assets to be Acquired and Liabilities to be Assumed. Adjustments included in the column under the heading “Pro Forma Adjustments” represent the following:

In addition, Centene assumed it would become subject to IRS Regulation 162(m)(6) beginning in 2015, with increased income tax expense for the nine months ended September 30, 2015 of approximately $21 million.

The following table summarizes the computation of the unaudited pro forma combined weighted average basic and diluted shares outstanding:

7. Balance Sheet Pro Forma Adjustments

This note should be read in conjunction with Note 1. Description of Transaction; Note 2. Basis of Presentation; Note 4. Estimate of Consideration Expected to be Transferred; and Note 5. Estimate of Assets to be Acquired and Liabilities to be Assumed. Adjustments included in the column under the heading “Pro Forma Adjustments” represent the following: