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and (ii) providing for the extinguishment of the outstanding Series E Preferred Shares immediately prior to the effective time of the merger.  A copy of the amended and restated articles supplementary reflecting the amendments is included as Annex D to the proxy statement/prospectus accompanying this notice;

·a proposal to approve, on a non-binding, advisory basis, merger-related compensation arrangements with CFS’s named executive officers; and

·a proposalapproval to adjourn the special meeting if necessaryto permit further solicitation in the event that an insufficient number of shares are present in person or appropriate,by proxy to solicit additional proxies in favor of the proposal to approve the merger agreement, the merger and the other transactions contemplated byadopt the merger agreement and the proposalstransactions contemplated thereby and appoint the shareholders’ representative and the alternate shareholders’ representative under the merger agreement; and

·                  to approvetransact any other business that properly comes before the amendments to the articles supplementary to the articles of incorporation for each series of CFS preferred stock providing for, among other matters, the preferred stock conversion.special meeting, or any adjournments or postponements thereof.

Holders of record of CFSSTC common stock Series C Preferred Shares, Series D Preferred Shares and Series E Preferred Shares at the close of business on      , 2015, which we refer to as the record date,2019 are entitled to receive this notice and to vote on one or more of these proposals at the special meeting and any adjournments or postponements or adjournments thereof.

Approval Adoption of the merger agreement and approval of the proposal to appoint Anthony V. Sisto and any successors thereto to serve as the shareholders’ representative upon the adoption of the merger agreement, including the appointment of Keith Kotche to serve as the alternate shareholders’ representative, each requires the affirmative vote at the special meeting of (i) two-thirdsholders of the outstanding shares of CFS common stock and Series C Preferred Shares (holders of Series C Preferred Shares casting the number of votes equal to the maximum number of shares of CFS common stock into which such holder’s Series C Preferred Shares are convertible as of the record date, without regard to any limitation on the conversion of such Series C Preferred Shares contained in the articles supplementary to the articles of incorporation of CFS for the Series C Preferred Shares), voting together as a single class, which we refer to as the outstanding voting securities, and (ii)at least a majority of the outstanding shares of each of (A) the Series C Preferred Shares, (B) the Series D Preferred Shares and (C) the Series E Preferred Shares.

STC common stock entitled to vote. Approval of the amendment to the articles supplementary to the articles of incorporation of CFS providing for, among other matters, the preferred stock conversion for the Series C Preferred Shares requires the affirmative vote of (i) two-thirds of the outstanding voting securities, (ii) a majority of the outstanding shares of CFS common stock and (iii) a majority of the outstanding Series C Preferred Shares. Approval of the amendment to the articles supplementary to the articles of incorporation of CFS providing for, among other matters, the preferred stock conversion for the Series D Preferred Shares requires the affirmative vote of (i) two-thirds of the outstanding voting securities and (ii) a majority of the outstanding Series D Preferred Shares.  Approval of the amendment to the articles supplementary to the articles of incorporation of CFS providing for, among other matters, the preferred stock conversion for the Series E Preferred Shares requires the affirmative vote of (i) two-thirds of the outstanding voting securities and (ii) a majority of the outstanding Series E Preferred Shares.

Approval of the proposals to approve merger-related compensation arrangements for CFS’s named executive officers andproposal to adjourn the special meeting, if necessary, or appropriate, requires in each case,the affirmative vote of holders of at least a majority of all the votes castshares of STC common stock entitled to vote, present in person or by the outstanding voting securities at the special meetingproxy, if a quorum is present. In the absence of a quorum, the holders of at least a majority of the outstanding voting securitiesshares of STC common stock present, in person or by proxy, at the special meeting may adjourn the special meeting.

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date of this proxy statement/prospectus, the merger consideration that a holder of CFS common stock (including holders of the shares of CFS preferred stock converted into shares of CFS common stock immediately prior to the effective time of the merger pursuant to the preferred stock conversion)STC shareholder would be entitled to receive for each share of CFSSTC common stock would be $      in cash and       shares of Wintrust common stock. In each case assuming no adjustment to the merger consideration and that the currently outstanding 10,781,988 shares of CFS common stock, 119,829 shares of Series C Preferred Shares, 65,427 shares of Series D Preferred Shares and 5,990 shares of Series E Preferred Shares (sometimes referred to in this proxy statement/prospectus collectively as CFS preferred stock) remain unchanged at the closing, and assuming the conversion of each share of CFS preferred stock into 100 shares of CFS common stock immediately prior to the completion of the merger pursuant to the preferred stock conversion, ifIf the reference price were less than or equal to the minimum of $42.50,$64.00, each share of CFSSTC common stock (including shares of CFS common stock issuable upon conversion of shares of CFS preferred stock immediately priorwould instead be entitled to the effective time of the merger pursuant to the preferred stock conversion) would be converted into the right to receive $0.71 in cash and 0.0170.781 shares of Wintrust common stock, and if the reference price were greater than or equal to the maximum of $52.50,$76.00, each share of CFSSTC common stock (including shares of CFS common stock issuable upon conversion of the shares of CFS preferred stock immediately prior to the effective time of the merger pursuant to the preferred stock conversion) would be converted into the rightentitled to receive $0.71 in cash and 0.0130.658 shares of Wintrust common stock. For a description of how the per share merger consideration will be calculated, see “The“Description of the Merger Agreement—Consideration to be received in the merger” on page 94.57.

$2,900,000 of the cash portion of the merger consideration, which we refer to as the escrowed funds, will be deposited in special purpose non-interest bearing escrow accounts, which we refer to as the escrow holdback. Pursuant to an escrow agreement entered into among Wintrust, the shareholders’ representative and The Chicago Trust Company, N.A., as escrow agent, which we refer to as the escrow agreement, $2,500,000, which we refer to as the escrow amount, will be held for a period of up to 15 months for the purposes of funding STC’s indemnification obligations under the merger agreement and supplementing the reserve amount referred to below by up to $500,000. Pursuant to a separate escrow agreement entered into among the shareholders’ representative, the litigation entity and The Chicago Trust Company, N.A., as escrow agent, which we refer to as the reserve agreement, $400,000, which we refer to as the reserve amount, will be deposited in a special purpose non-interest bearing account to fund the shareholders’

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approve merger-related compensation arrangements with CFS’s named executive officers and “FOR” the proposalapproval to adjourn the special meeting to permit further solicitation in the event that an insufficient number of proxiesshares are present in favor of the merger agreement, the merger and the other transactions contemplatedperson or by proxy to adopt the merger agreement and the amendments totransactions contemplated thereby and appointment of the articles supplementary toshareholders’ representative and the articles of incorporation of CFS for each series of CFS preferred stock providing for, among other matters, the preferred stock conversion.  The CFSalternate shareholders’ representative. STC’s board of directors has determined that the merger agreement and the merger and the amendments to the articles supplementary to the articles of incorporation of CFS for each series of CFS preferred stock providing for, among other matters, the preferred stock conversion are advisable and in the best interests of CFS.STC and its shareholders. To review the background and reasons for the merger in greater detail, see “The Merger” beginning on page 63.29.

Q:What vote is required to approveadopt the merger?merger agreement?

A:The affirmative vote                                   Holders of two-thirds of the outstanding shares of CFS common stock and Series C Preferred Shares (holders of Series C Preferred Shares casting the number of votes equal to the maximum number of shares of CFS common stock into which such holder’s Series C Preferred Shares are convertible as of the record date, without regard to any limitation on the conversion of such Series C Preferred Shares contained in the articles supplementary to the articles of incorporation for the Series C Preferred Shares), voting together as a single class, which we refer to collectively as the outstanding voting securities, is required to approve the merger agreement, the merger and the other transactions contemplated by the merger agreement.  In addition,at least a majority of the outstanding shares of eachSTC common stock entitled to vote must vote in favor of the Series C Preferred Shares, the Series D Preferred Shares and the Series E Preferred Shares is required to approve the merger agreement, the merger and the other transactions contemplated by the merger agreement.merger. Abstentions and failures to votebroker non-votes have the effect of votes against the approvaladoption of the merger agreement, the merger and the other transactions contemplated by the merger agreement.

Even if the merger agreement, the merger and the other transactions contemplated by the merger agreement receive the requisite votes for approval, the merger will not be completed unless CFS stockholders also approve the amendments to the articles supplementary to the articles On June 5, 2019, certain of incorporationSTC’s directors who own shares of CFS for each series of CFS preferredSTC common stock providing for, among other matters, the preferred stock conversion.

All of the directors and officers of CFS and certain other stockholders of CFS entered into voting agreements pursuant to which they agreed to vote their CFS shares at the special meeting in favor of the merger and any other matter necessary for consummation of the transactions contemplated by the merger agreement (including the amendments to the articles supplementary to the articlesagreement. These shareholders and their affiliates owned approximately 46% of incorporation of CFS for each series of CFS preferred stock providing for, among other matters, the preferred stock conversion).  The shares subject to the voting agreement represent approximately 10.7% of the outstanding shares of CFSSTC common stock 31.5% of the outstanding voting securities, 50.1% of the outstanding Series C Preferred Shares, 89.1% of the outstanding Series D Preferred Shares and 0% of the outstanding Series E Preferred Shares, each as of April 28, 2015.  No vote ofJune 5, 2019. Wintrust’s shareholders is required in connection with the transactions contemplated bywill not be voting on the merger agreement. See “The Merger—Interests of certain persons in the merger” on page 8952 and “The Merger—Voting agreement” on page 91.53.

Q:What vote is required to approveappoint the amendmentsshareholders’ representative and the alternate shareholders’ representative upon adoption of the articles supplementary to the articles of incorporation of CFS providing for, among other matters, the preferred stock conversion with respect to the Series C Preferred Shares?merger agreement?

A:The affirmative vote                                   Holders of two-thirds of the outstanding voting securities is required to approve the proposed amendments, collectively referred to as the amendment, to the articles supplementary to the articles of incorporation of CFS with respect to the Series C Preferred Shares.

Additionally, the articles supplementary to the articles of incorporation of CFS for the Series C Preferred Shares require that the proposed amendment thereto be approved by each of (i) a majority of the outstanding Series C Preferred Shares and (ii)at least a majority of the outstanding shares of STC common stock.stock entitled to vote must vote in favor of the appointment of Anthony V. Sisto and any successors thereto as shareholders’ representative upon adoption of the merger agreement, including the appointment of Keith Kotche as alternate shareholders’ representative. Abstentions and failures to votebroker non-votes have the effect of votes against the approvalappointment of the proposal to approve the

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amendment to the articles supplementary to the articles of incorporation of CFS providing for, among other matters, the preferred stock conversion with respect to the Series C Preferred Shares.

Even if the amendment of the articles supplementary to the articles of incorporation of CFS providing for, among other matters, the preferred stock conversion with respect to the Series C Preferred Shares receives the requisite votes for approval, the merger and the preferred stock conversion will not be completed unless CFS stockholders also approve the merger agreement, the mergerincluding Mr. Kotche as alternate shareholders’ representative. If a shareholder does not vote in favor of appointing Mr. Sisto and the other transactions contemplated byany successors thereto as shareholders’ representative upon adoption of the merger agreement, including Mr. Kotche as alternate shareholders’ representative, but Mr. Sisto and Mr. Kotche nonetheless receive the other amendments to the articles supplementary to the articlesapproval of incorporation of CFS providing for, among other matters, the preferred stock conversion.

See “The Merger—Interests of certain persons in the merger” on page 89 and “The Merger—Voting agreement” on page 91 forat least a descriptionmajority of the votingoutstanding shares of STC common stock entitled to vote, Mr. Sisto and any successors thereto will serve as the shareholders’ representative for all shareholders upon adoption of the merger agreement, entered into by all directors and officersincluding Mr. Kotche as the alternate shareholders’ representative, regardless of CFS and certain other stockholders of CFSwhether a particular shareholder may have voted for such individuals to serve in connection with the proposed merger transaction.that capacity.

Q:What vote is required to approve the amendments of the articles supplementary to the articles of incorporation of CFS providing for, among other matters, the preferred stock conversion with respect to the Series D Preferred Shares?

A:The affirmative vote of two-thirds of the outstanding voting securities is required to approve the proposed amendments, collective referred to as the amendment,  to the articles supplementary to the articles of incorporation of CFS with respect to the Series D Preferred Shares.

Additionally, the articles supplementary to the articles of incorporation of CFS for the Series D Preferred Shares require that this proposed amendment be approved by a majority of the outstanding Series D Preferred Shares.  Abstentions and failures to vote have the effect of votes against the approval of the proposal to approve the amendment of the articles supplementary to the articles of incorporation of CFS providing for, among other matters, the preferred stock conversion with respect to the Series D Preferred Shares.

Even if the amendment of the articles supplementary to the articles of incorporation of CFS providing for, among other matters, the preferred stock conversion with respect to the Series D Preferred Shares receives the requisite votes for approval, the merger and the preferred stock conversion will not be completed unless CFS stockholders also approve the merger agreement, the merger and the other transactions contemplated by the merger agreement and the other amendments to the articles supplementary to the articles of incorporation of CFS providing for, among other matters, the preferred stock conversion.

See “The Merger—Interests of certain persons in the merger” on page 89 and “The Merger—Voting agreement” on page 91 for a description of the voting agreement entered into by all directors and officers of CFS and certain other stockholders of CFS in connection with the proposed merger transaction.

Q:What vote is required to approve the amendments of the articles supplementary to the articles of incorporation of CFS providing for, among other matters, the preferred stock conversion with respect to the Series E Preferred Shares?

A:The affirmative vote of two-thirds of the outstanding voting securities is required to approve the proposed amendments, collectively referred to as the amendment, to the articles supplementary to the articles of incorporation of CFS with respect to the Series E Preferred Shares.

Additionally, the articles supplementary to the articles of incorporation of CFS for the Series E Preferred Shares require that this proposed amendments be approved by a majority of the outstanding Series E Preferred Shares.  Abstentions and failures to vote have the effect of votes against the approval of the proposal to approve the amendment of the articles supplementary to the articles of incorporation of CFS

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providing for, among other matters, the preferred stock conversion with respect to the Series E Preferred Shares.

Even if the amendment of the articles supplementary to the articles of incorporation of CFS providing for, among other matters, the preferred stock conversion with respect to the Series E Preferred Shares receives the requisite votes for approval, the merger and the preferred stock conversion will not be completed unless CFS stockholders also approve the merger agreement, the merger and the other transactions contemplated by the merger agreement and the other amendments to the articles supplementary to the articles of incorporation of CFS providing for, among other matters, the preferred stock conversion.

See “The Merger—Interests of certain persons in the merger” on page 89 and “The Merger—Voting agreement” on page 91 for a description of the voting agreement entered into by all directors and officers of CFS and certain other stockholders of CFS in connection with the proposed merger transaction.

Q:What vote is required to approve the proposal to approve, on a non-binding, advisory basis, merger-related compensation arrangements with CFS’s named executive officers?

A:A majority of all votes cast by the outstanding shares of CFS common stock and Series C Preferred Shares (holders of Series C Preferred Shares casting the number of votes equal to the maximum number of shares of CFS common stock into which such holder’s Series C Preferred Shares are convertible as of the record date, without regard to any limitation on the conversion of such Series C Preferred Shares contained in the articles supplementary to the articles of incorporation of CFS for the Series C Preferred Shares), voting together as a single class, at the special meeting at which a quorum is present is required to approve, on a non-binding, advisory basis, merger-related compensation arrangements with CFS’s named executive officers. Abstentions and failures to vote will have no effect on the approval of the proposal to approve, on a non-binding, advisory basis, merger-related compensation arrangements with CFS’s named executive officers.

Q:What vote is required to approve the proposal to adjourn the special meeting if necessary or appropriate, to permit further solicitation in the event that an insufficient number of proxiesshares are present in favor of the merger agreement, the merger and the other transactions contemplatedperson or by proxy to adopt the merger agreement and the amendments to the articles supplementary to the articles of incorporation of CFS providing for, among other matters, the preferred stock conversion?transactions contemplated thereby?

A:A majority of the votes cast by of the outstanding shares of common stock and Series C Preferred Shares (holders of shares of such Series C Preferred Shares casting the number of votes equal to the maximum number of shares of CFS common stock into which such holder’s Series C Preferred Shares are convertible as of the record date, without regard to any limitation on the conversion of such Series C Preferred Shares contained in the articles supplementary for the Series C Preferred Shares), voting together as a single class, if a quorum is present at the special meeting, is required to approve the                                   The proposal to adjourn the special meeting, if necessary or appropriate to solicit additional proxies, requires the affirmative vote of at least a majority of the shares of STC common stock entitled to approvevote, present in person or by proxy, if a quorum is present at the merger agreement, the merger, the transactions contemplated by the merger agreement and the amendments to the articles supplementary to the articles of incorporation of CFS providing for, among other matters, the preferred stock conversion.special meeting. In the absence of a quorum, holders of at least a majority of the outstanding voting securitiesshares of STC common stock present in person or by proxy at the special meeting may adjourn the special meeting. Abstentions and failures to vote will have nothe effect onof votes against the proposal, to adjourn the meeting, if necessary or appropriate, to solicit additional proxies in favor of the merger agreement, the merger and the other transactions contemplated by the merger agreement and the amendments to the articles supplementary to the articles of incorporation.

Q:What constitutes a quorum for purposes of the special meeting?

A:CFS’s by-laws provide that a majority of the outstanding securities of CFSbroker non-votes will not be considered entitled to vote represented in person or by proxy, shall constitute a quorum.  Abstentions are treated as present at the meeting for purposes of determining whether a quorum is present.  If you hold your shares in “street name” and do not provide your broker or other nominee with instructions and your broker or other nominee does not submit a

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proxy card or otherwise does not vote because the broker or other nominee lacks discretionary authority to vote the shares, your shares will not be counted for purposes of determining a quorum and they will have the same effect as a vote against the proposal to approve the merger agreement, the merger and the other transactions contemplated by the merger agreement and the proposals to approve the amendments to the articles supplementary to the articles of incorporation of CFS providing for the preferred stock conversion, as the case may be, and will have no effect on the proposal to approve, on a non-binding, advisory basis, merger-related compensation arrangements with CFS’s named executive officers proposal or the proposal to adjourn the special meeting, if necessary or appropriate.proposal.

Q:Why is my vote important?

A:CFS stockholders                                   STC’s shareholders are being asked to approve, among other things, the merger agreement, the merger and the other transactions contemplated byadopt the merger agreement and the amendments to the articles supplementary to the articles of incorporation of CFS providing for, among other matters, the preferred stock conversion.  Approval of the merger agreement, the merger and the other transactions contemplated by the merger agreement and the amendments to the articles supplementary to the articles of incorporation of CFS providing for, among other matters, the preferred stock conversion are closing conditions tothereby approve the merger.  If all of the required stockholder approvals are not obtained, the merger will not occur. If you do not submit your proxy by mail telephone or via the Internet, or vote in person at the special meeting, it will be more difficult for CFSSTC to obtain the necessary quorum to hold the special meeting. In addition, your failure to submit your proxy or attend the special meeting will have the same effect as a vote against the merger agreement the merger and other transactions contemplated by the merger agreement and the amendments to the articles of supplementary to the articles of incorporation of CFS providing for, among other matters, the preferred stock conversion and make it more difficult to obtain approvaladoption of the merger agreement, the merger and other transactions contemplated by the merger agreement and the amendments to the articles supplementary to the articles of incorporation of CFS providing for, among other matters, the preferred stock conversion.agreement.

Q:What do I need to do now? How do I vote?

A:You may vote on all matters presented at the special meeting if you own shares of CFSSTC common stock or Series C Preferred Shares of record at the close of business on the record date for the special meeting,      , 2015.  You may vote on (i)2019. After you have carefully read and considered the proposal to approve the merger agreement, the mergerinformation contained in this proxy statement/prospectus, please complete, sign, date and the other transactions contemplated by the merger agreement and (ii) the proposal to approve an amendment to the articles supplementary to the articles of incorporation of CFS for the Series D Preferred Shares that provides for the conversion of the Series D Preferred Shares into common stock if you own Series D Preferred Shares of record at the close of business on the record date for the special meeting,          , 2015.  You may vote on (i) the proposal to approve the merger agreement, the merger and the other transactions contemplated by the merger agreement and (ii) the proposal to approve an amendment to the articles supplementary to the articles of incorporation of CFS for the Series E Preferred Shares that provides for the conversion of the Series E Preferred Shares into common stock if you own Series E Preferred Shares of record at the close of business on the record date for the special meeting,           , 2015.

CFS stockholders of record may vote now bymail your proxy by:

·completing, signing, dating and returningform in the enclosed proxy card in the accompanying pre-addressed postage-paid envelope;

·calling the toll-free number specified on your proxy card; or

·accessing the Internet website specified on your proxy card.

A CFS stockholder has the right to appoint a person (who need not be a stockholder)prepaid return envelope as proxy holder to attend and act on his, her or its behalf at the special meeting, other than the CFS representatives of management and the CFS board of directors designated in the form of proxy.  The CFS stockholder may

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exercise this right by completing another appropriate form of proxy and delivering the completed proxy in the manner set forth above.

We strongly encourage you to vote using the proxy card provided by CFS.

If you hold shares of CFS in “street name,” which meanssoon as possible. This will enable your shares are held of record by a broker, bank or nominee, you must provide the record holder of your shares with instructions on how to vote your shares.  Please refer to the voting instruction card used by your broker, bank or nominee to see if you may submit voting instructions using the Internet or telephone.

Additionally, you may also vote in person by attending the special meeting.  If you plan to attend the special meeting and wish to vote in person, you will be given a ballotrepresented at the special meeting. Please note, however, that if your shares are held in “street name,” and you wish toYou may also vote in person at the special meeting,meeting. If you must bringdo not return a properly executed proxy from the record holder of the shares authorizing you toform and do not vote at the special meeting. Whether or not you plan to attendmeeting, this will have the special meeting, you are encouraged to grant your proxysame effect as described in this proxy statement/prospectus.a vote against the adoption of the merger agreement.

Q:How will my proxy be voted?

A:If you vote via the Internet or complete, sign, date and mail your proxy form, your proxy will be voted in accordance with your instructions. If you sign, date and send in your proxy form, but you do not indicate how you want to vote, your proxy will be voted “FOR” the proposal to approveFOR adoption of the merger agreement the merger and the other transactions contemplated by the merger agreement, the proposals to approve the amendments to the articles supplementary to the articles of incorporation of CFS providing for, among other matters, the preferred stock conversion and the other proposals in the notice.

Q:Can I revoke my proxy and change my vote?

A:You canmay change your vote or revoke your proxy at any time before it is voted by filing with the secretary of STC a duly executed revocation of proxy or submitting a new proxy form with a later date. You may also revoke a prior proxy by voting in person at the special meeting by any of the following methods:

·Submitting a later-dated proxy by mail.

·Sending a written notice of revocation of proxy, prior to the taking of the vote at the meeting, to the Corporate Secretary of CFS at:

Community Financial Shares, Inc.

357 Roosevelt Road

Glen Ellyn, Illinois 60137

Attention: Christopher P. Barton, Secretary

Facsimile: (630) 545-0399

·Attending the special meeting and voting in person, although your attendance at the special meeting will not in and of itself revoke your proxy. You must also vote your shares at the meeting.

If your shares are held in the name of a bank, broker or other record holder, you must obtain a proxy, executed in your favor, from the record holder to be able to vote at the annual meeting.  CFS stockholders must contact their broker, bank or other nominee to find out how to do so.

Q:What if I oppose the merger? Do I have appraisaldissenters’ rights?

A:CFS stockholders                                   STC shareholders who do not vote in favor of approvaladoption of the merger agreement and who otherwise comply with all of the procedures of Title 3, Subtitle 2Sections 11.65 and 11.70 of the Maryland GeneralIllinois Business Corporation Law,Act, which we refer to as the MGCL,IBCA, will be entitled to receive payment in cash of the fair value of their shares of CFSSTC common stock including common stock issued upon conversion of preferred stock into common stock prior to the merger,

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as ultimately determined under the statutory process. A copy of the relevantthese sections of the MGCLIBCA is attached as Annex EB to this document.

Q:What if I oppose the preferred stock conversion?  Do I have appraisal rights?

A:CFS stockholders who do not vote in favor of approval of the amendments to the articles supplementary to the articles of incorporation of CFS providing for, among other matters, the preferred stock conversion are not entitled to appraisal rights.

Q:What are the tax consequences of the merger to me?

A:In general, each                                   STC and Wintrust intend for the merger to qualify as a “reorganization” pursuant to Section 368(a) of the conversionInternal Revenue Code of your shares of CFS common stock into Wintrust common stock in1986, as amended, which we refer to as the Code. Provided the merger and the automatic conversion of the Series C Preferred Shares, Series D Preferred Shares and Series E Preferred Shares into CFS common stock immediately prior to the effective time of the merger is intended to be tax-freequalifies as a reorganization for United States federal income tax purposes.  However,purposes, you generallymay recognize gain, but will not recognize loss, upon the exchange of your shares of STC common for shares of Wintrust common stock and cash.  If the sum of the fair market value of the Wintrust common stock and the amount of cash you receive in exchange for your shares of STC common stock exceeds the adjusted basis of your shares of STC common stock, you will recognize taxable gain (but not loss) in anequal to the lesser of the amount limited toof such excess or the amount of cash you receive in the merger.exchange. Additionally, you will recognize gain or loss on any cash that you receive in lieu of fractional shares of Wintrust’s common stock. Generally, any gain recognized upon the exchange will be capital gain, and any such capital gain will be long-term capital gain if you have established a holding period of more than one year for your shares of STC common stock.  Depending on certain facts specific to you, any gain could instead be characterized as ordinary dividend income.  You should consult with your tax adviser for the specific tax consequences of the merger to you. See “The Merger—Material U.S. federal income tax consequences of the merger” on page 85.49.

Q:When and where is the special meeting?

A:CFS’s                                   The STC special meeting will take place on      , 2015,2019, at       local time, at       .

Q:Who may attend the meeting?

A:CFS stockholders                                   STC shareholders on the record date may attend the special meeting. If you are a stockholdershareholder of record, you may need to present proof of identification in order to be admitted into the meeting.

Q:Should I send in my stock certificates now?

A:No. After the merger is completed, the exchange agent for the merger will send you a letter of transmittal with instructions informing you how to send in your stock certificates to the exchange agent. You should use the letter of transmittal to exchange your CFSSTC stock certificates for the merger consideration. Do not send in your stock certificates with your proxy form.

Q:When is the merger expected to be completed?

A:We will try to complete the merger as soon as reasonably possible. Before that happens, the merger agreement the merger and the other transactions contemplated by the merger agreement and the amendments to the articles supplementary to the articles of incorporation of CFS providing for, among other matters, the preferred stock conversion must be approvedadopted by CFS stockholders,STC’s shareholders and we must obtain the appropriatenecessary regulatory approvals. Assuming stockholdersshareholders vote to approve the merger agreement, the merger and the other transactions contemplated byadopt the merger agreement and the amendments to the articles supplementary to the articles of incorporation of CFS providing for, among other matters, the preferred stock conversion, and assuming we obtain the other appropriatenecessary approvals and satisfaction or waiver of the other conditions to the closing described in the merger agreement, we expect to complete the merger in the second or third quarter of 2015.2019. See “The“Description of the Merger Agreement—Conditions to completion of the merger” on page 108.65.

Q:                                  Is completion of the merger subject to any conditions besides stockholder approval of the merger agreement, the merger and the other transactions contemplated by the merger agreement and the amendments to the articles supplementary to the articles of incorporation of CFS providing for, among other matters, the preferred stock conversion?shareholder approval?

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A:Yes. The transaction must receive appropriatethe required regulatory approvals, and there are other closing conditions that must be satisfied. See “The“Description of the Merger Agreement—Conditions to completion of the merger” on page 108.65.

Q:Are there risks I should consider in deciding to vote on the approvaladoption of the merger agreement, the merger and the other transactions contemplated by the merger agreement, the amendments to the articles supplementary to the articles of incorporation of CFS providing for, among other matters, the preferred stock conversion and other proposals contained in this proxy statement/prospectus?agreement?

A:Yes, in evaluating the merger agreement, the merger and the other transactions contemplated by the merger agreement and the amendment to the articles supplementary to the articles of incorporation of CFS providing for, among other matters, the preferred stock conversion, you should read this proxy statement/prospectus carefully, including the factors discussed in the section titled “Risk Factors” beginning on page 27.19.

Q:Who can answer my other questions?

A:If you have more questions about the merger or how to submit your proxy, or if you need additional copies of this proxy statement/prospectus or the enclosed proxy form, you should contact Christopher P. Barton, CFS’s Corporate SecretaryAnthony V. Sisto, STC’s Chairman, at (630) 545-0900.377-1555, or Christopher Woelffer, STC’s President, at (630) 463-4333.

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