SUPPLEMENTAL PENSION PLAN OFTIMKENSTEEL CORPORATION (Effective June 30, 2014)

EXHIBIT 10.1

SUPPLEMENTAL PENSION PLAN

OF TIMKENSTEEL CORPORATION

(Effective June 30, 2014)

TimkenSteel Corporation (the “Company”) hereby adopts the Supplemental Pension Plan of TimkenSteel Corporation (the “Supplemental Plan”), effective June 30, 2014, for the purpose and in accordance with the provisions as set forth below. The Supplemental Plan was formed as a result of a spin-off and transfer of the liabilities, effective June 30, 2014 (the “Split Date”), from the Amended and Restated Supplemental Pension Plan of The Timken Company (Amended and Restated Effective June 1, 2013) (the “Timken Supplemental Plan”) attributable to the benefits accrued for Transferred Participants under the Timken Supplemental Plan. The Supplemental Plan is a continuation of and a successor plan to the Timken Supplemental Plan solely with respect to such Transferred Participants. Effective as of the Split Date, the Transferred Participants shall cease to be participants in the Timken Supplemental Plan and shall become participants under this Supplemental Plan, and the terms of this Supplemental Plan will govern the benefits accrued by Transferred Participants under the Timken Supplemental Plan prior to the Split Date. Any election, waiver, consent, or designation made by a Participant, a Spouse, a DOMA Spouse or Lump Sum Beneficiary under the Timken Supplemental Plan prior to the Split Date that was recognized as valid by the Timken Supplemental Plan immediately prior to the Split Date will be recognized by this Supplemental Plan as a valid election, waiver, consent, or designation, as applicable.

The purpose of the Supplemental Plan is to provide for, on or after the effective date hereof, the payment of supplemental retirement benefits:

(a) to those participants of the TimkenSteel Corporation Retirement Plan (the “Qualified Plan”) whose benefits payable under the Qualified Plan are subject to certain benefit limitations imposed by ERISA and Section 401 and Section 415 of the Code (collectively referred to as “Code Limitations”); and

(b) to certain employees of the Company who have Employee Excess Benefits Agreements (“Excess Agreements”) that have been assumed by, and are in effect with, the Company.

Each of the following individuals shall be eligible for benefits under the Supplemental Plan and shall be known as a “Participant”:

(a) Members of or participants in the Qualified Plan but only to the extent the members or participants are members or participants pursuant to Part Seven, Part Eight, Part Ten and Part Fifteen of the Qualified Plan, other than participants described in paragraph 2(d), who are eligible for a retirement benefit other than a deferred vested pension and whose retirement benefits under the Qualified Plan are limited pursuant to the Code Limitations;

(b) Transferred Participants who were members of or participants in the Timken Supplemental Plan as of the close of business on the Split Date, the liability for whose benefit was spun-off from the Timken Supplemental Plan to this Supplemental Plan effective as of the Split Date, other than participants described in paragraph 2(d), who are eligible for a retirement benefit other than a deferred vested pension and whose retirement benefits under the Qualified Plan are limited pursuant to the Code Limitations;

(c) (i) Former employees of the Company who separated from the service of the Company, and (ii) current employees of the Company who separate from the service

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of the Company, in each case under circumstances which the Company, in its sole discretion, deems to be for mutually satisfactory reasons and in each case with eligibility for a deferred vested pension and whose retirement benefits under the Qualified Plan are limited by the Code Limitations; and

(d) Employees of the Company who have Excess Agreements currently in effect with the Company.

The Qualified Plan, with any amendments thereto, is hereby incorporated by reference into and shall be a part of the Supplemental Plan as fully as if set forth herein. Any future amendment made to the Qualified Plan shall be also incorporated by reference into and form a part of the Supplemental Plan, effective as of the effective date of such amendment. The Qualified Plan, whenever referred to in the Supplemental Plan, shall mean such Qualified Plan as it exists as of the date any determination is made of benefits payable under the Supplemental Plan. All terms used herein shall have the meanings assigned to them under the provisions of the Qualified Plan unless otherwise qualified by the context of the Supplemental Plan. If there is any conflict between the provisions of the Qualified Plan and the provisions of the Supplemental Plan, the provisions of the Supplemental Plan will govern.

(a) The benefit payable to a Participant described in paragraphs 2(a), (b) or (c) under the Supplemental Plan shall be equal to the excess, if any, of:

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Such benefits payable under the Supplemental Plan to any Participant shall be computed in accordance with the foregoing using the normal form of payment under the Qualified Plan and with the objective that such Participant should receive under the Supplemental Plan and the Qualified Plan the total amount which would otherwise have been payable to that Participant solely under the Qualified Plan had not the Code Limitations been applicable thereto. The Participant’s benefit under the Supplemental Plan will be paid in the form provided under paragraph 5(a). If any portion of a Participant’s benefit under the Qualified Plan is not payable at the same time the Participant’s benefit under the Supplemental Plan is payable, for purposes of this paragraph 4, the corresponding portion of the benefit under the Supplemental Plan shall be determined by calculating that portion of the benefit that would be payable under the Supplemental Plan and Qualified Plan at age 65 and then actuarially reducing such benefit from age 65 to the commencement date provided under the Supplemental Plan in accordance with paragraph 5(b). Any actuarial adjustments under this paragraph 4 shall be based on the Plan Assumptions and, for this purpose, the determinations made under this paragraph 4(a) will be made in the calendar year in which the Participant has a separation from service (as defined in paragraph 5).

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(b) The benefit payable to a Participant described in paragraph 2(d) under the Supplemental Plan shall be the benefit described in such Participant’s Excess Agreement.

(c)

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(a) Form of Payment.

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If a Participant elects an Optional Form that provides for a benefit to a joint pensioner or beneficiary, such joint pensioner or beneficiary shall be designated at the time the Participant elects such Optional Form. If a Participant has a DOMA Spouse and wants to designate a joint pensioner or beneficiary other than his or her DOMA Spouse, such designation will not take effect unless (i) the Participant’s DOMA Spouse consents in writing to such election, the election designates a beneficiary or a form of benefits which may not be changed without spousal consent (or the consent of the DOMA Spouse expressly permits designations by the Participant without any requirement of further consent by the DOMA Spouse), and the DOMA Spouse’s consent acknowledges the effect of such election and is witnessed by a Plan representative or a notary public,

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or (ii) it is established to the satisfaction of a Plan representative that the consent required under (i) cannot be obtained because there is no DOMA Spouse, because the DOMA Spouse cannot be located, or because of such other circumstances as the Secretary of the Treasury may prescribe by regulations. Any consent by a DOMA Spouse or establishment that the consent of a DOMA Spouse may not be obtained shall be effective only with respect to such DOMA Spouse.

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(b) Time of Payment.

(c) Delayed Benefits for Specified Employees. Notwithstanding any provision of this Supplemental Plan to the contrary, if a Participant is a “specified employee,” determined pursuant to procedures adopted by the Company in compliance

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with Section 409A of the Code, on the date the Participant separates from service, then to the extent necessary to comply with Section 409A, amounts that would otherwise be payable pursuant to this Supplemental Plan during the six-month period immediately following the Participant’s separation from service will instead be paid or made available on the earlier of (i) the first business day of the seventh month after the date of the Participant’s separation from service, or (ii) the Participant’s death. Any benefit payments that are scheduled to be paid more than six months after such Participant’s separation from service shall not be delayed and shall be paid in accordance with the schedule prescribed by paragraphs 5(a) and 5(b).

(d) Small Benefit Cash-Out. Notwithstanding any provision to the contrary but subject to paragraph 5(c), if, upon a Participant’s separation from service, the actuarial present value of the benefit the Participant is entitled to receive under this Supplemental Plan and any other plans with respect to which deferrals of compensation are treated as having been deferred under a single nonqualified deferred compensation plan with the Supplemental Plan under Treasury Regulation Section 1.409A-1(c)(2) (the “Aggregate Benefit”) is less than $15,000, the Company may in its discretion pay the Participant’s entire Aggregate Benefit in a single lump sum payment on the 30^th day following the Participant’s separation from service. To determine the Aggregate Benefit under this paragraph 5(d), the Plan Assumptions will be used.

(e) Separation from Service. For purposes of this paragraph 5, “separation from service” or “separates from service” shall mean termination of employment (within the meaning of Treasury Regulation Section 1.409A-1(h)(1)(ii)) with the Company and any member of its controlled group (as such term is used for purposes of ERISA and the

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Code, except that a 50% ownership or common control threshold shall be used to determine controlled group status instead of an 80% ownership or common control threshold). For purposes of the preceding sentence a termination of employment shall also include a permanent decrease in the level of bona fide services performed by the Participant after a certain date to a level that is 20% or less of the average level of bona fide services performed by the Participant over the immediately preceding 36-month period.

(a) “Aggregate Benefit” shall have the meaning given to such term in paragraph 5(d).

(b) “Average Interest Rate” means the single effective interest rate which results in the same lump sum amount for a benefit paid in the Lump Sum Option as results from use of the “applicable interest rate” as defined under “Plan Assumptions.”

(c) “Claimant” shall have the meaning given to such term in paragraph 8(c).

(d) “Code” means the Internal Revenue Code of 1986, as amended.

(e) “Code Limitations” shall have the meaning given to such term in paragraph 1(a).

(f) “Company” shall have the meaning given to such term in the preamble.

(g) “Competitive Activity” shall have the meaning given to such term in paragraph 10.

(h) “Delayed Payment Date” shall have the meaning given to such term in paragraph 5(a)(iv)(B).

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(i) “DOMA Spouse” means a Spouse who is a person of the opposite gender to whom a Participant is legally married under the laws of a U.S. state or foreign nation (including common law marriages if recognized by the laws of the U.S. state in which the Participant resides).

(j) “Initial Election” means a Participant’s election to receive his or her benefit in a Lump Sum Option in accordance with the requirements of paragraph 5(a)(iii).

(k) “ERISA” means the Employee Retirement Income Security Act of 1974, as amended.

(l) “Excess Agreements” shall have the meaning given to such term in paragraph 1(b).

(m) “Optional Forms” shall have the meaning given to such term in paragraph 5(a)(i).

(n) “Life Annuity” shall have the meaning given to such term in paragraph 5(a)(i).

(o) “Lump Sum Beneficiary” means the beneficiary the Participant designates on a written form acceptable to the Company, in its discretion, provided that if a Participant has a DOMA Spouse on the date of such designation and designates a Lump Sum Beneficiary who is not the Participant’s DOMA Spouse, that DOMA Spouse must have provided consent to such designation in accordance with the consent requirements set forth under paragraph 5(a)(i). If a Participant has not designated a Lump Sum Beneficiary in accordance with the preceding sentence, the Participant’s Lump Sum Beneficiary shall be his or her Spouse on the Participant’s date of death or, if there is no such Spouse, the Participant’s estate. If the Participant has obtained the consent of the

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individual who is his or her DOMA Spouse on the date the applicable Lump Sum Beneficiary is designated, the Participant will not be required to obtain the consent of any later Spouse for the prior designation of the Lump Sum Beneficiary. Notwithstanding any provision of the Plan to the contrary, if the Participant has designated his or her Spouse as a Lump Sum Beneficiary, that designation shall terminate and be of no further force and effect as of the date the individual ceases to be the Spouse of the Participant as result of divorce, dissolution, or other legal termination of the relationship.

(p) “Lump Sum Option” shall have the meaning given to such term in paragraph 5(a)(iii)(A).

(q) “Participant” shall have the meaning given to such term in paragraph 2.

(r) “Plan Assumptions” means the “applicable mortality table, “ as defined in Code Section 417(e)(3) and the “applicable interest rate” as defined in Code Section 417(e)(3), during the third calendar month (October) immediately preceding the first day of the calendar year in which the determination is made.

(s) “Qualified Plan” shall have the meaning given to such term in paragraph 1(a).

(t) “Spouse” shall have the meaning given to such term in the Qualified Plan.

(u) “Subsequent Election” means a Participant’s election to receive his or her benefit in a Lump Sum Option in accordance with the requirements of paragraph 5(a)(iv).

(v) “Supplemental Plan” shall have the meaning given to such term in the preamble.

(w) “Transferred Participant” shall have the meaning given to such term in the Qualified Plan.

(x) “Transition Election” shall have the meaning given to such term in paragraph 5(b)(i).

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(a) The entire cost of the Supplemental Plan shall be paid from the general assets of the Company. It is the intent of the Company to so pay benefits under the Supplemental Plan as they become due; provided, however, that the Company may, in its sole discretion, establish or cause to be established a trust account for any or each Participant pursuant to an agreement, or agreements, with a bank and direct that some or all of a Participant’s benefits under the Supplemental Plan be paid from the general assets of the Company which are transferred to the custody of such bank to be held by it in such trust account as property of the Company subject to the claims of its creditors until such time as benefit payments pursuant to the Supplemental Plan are made from such assets in accordance with such agreement; and until any such payment is made, neither the Plan nor any Participant, Spouse or other beneficiary shall have any preferred claim on, or any beneficial ownership interest in, such assets. Notwithstanding any provision of the Supplemental Plan to the contrary, no amounts shall be so transferred to a trust pursuant to the preceding sentence if, pursuant to Section 409A(b)(3)(A) of the Code, such amount would, for purposes of Section 83 of the Code, be treated as property transferred in connection with the performance of services. No liability for the payment of benefits under the Supplemental Plan shall (i) be imposed upon any officer, director, employee, or stockholder of the Company, (ii) be imposed upon the trust fund under the Qualified Plan, (iii) be paid from the trust fund under the Qualified Plan, or (iv) have any effect whatsoever upon the Qualified Plan or the payment of benefits from the trust fund under the Qualified Plan.

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(b) No right or interest of a Participant, Spouse or other beneficiary under the Supplemental Plan shall be anticipated, assigned (either at law or in equity), or alienated by the Participant, Spouse or other beneficiary, nor shall any such right or interest be subject to attachment, garnishment, levy, execution, or other legal or equitable process or in any manner be liable for or subject to the debts of any Participant, Spouse or other beneficiary. The Company shall not recognize any attempt by any Participant, Spouse or other beneficiary to alienate, sell, transfer, assign, pledge, or otherwise encumber his or her benefits under the Supplemental Plan or any part thereof. To the extent permitted by Section 409A of the Code, this paragraph 7(b) shall not apply, however, in the case of a domestic relations order that would be a “qualified domestic relations order” within the meaning of Section 206(d)(3) of ERISA if the Supplemental Plan was subject to Section 206(d)(3) of ERISA. Except as permitted under Section 409A of the Code, any deferred compensation (within the meaning of Section 409A of the Code) payable to a Participant or for a Participant’s benefit under this Supplemental Plan may not be reduced by, or offset against, any amount owing by a Participant to the Company or any of its affiliates.

(c) Employment rights shall not be enlarged or affected hereby. The Company shall continue to have the right to discharge or retire a Participant, with or without cause.

(a) The Company shall, in its discretion, interpret where necessary, in its reasonable and good faith judgment, the provisions of the Supplemental Plan and, except as otherwise provided in the Supplemental Plan, shall determine the rights and status of Participants, Spouses and other beneficiaries hereunder (including, without limitation, the amount of any benefit to which a Participant or beneficiary may be entitled under the

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Supplemental Plan). Except to the extent federal law controls, all questions pertaining to the construction, validity, and effect of the provisions hereof shall be determined in accordance with the laws of the State of Ohio.

(b) The Company may, from time to time, delegate all or part of the administrative powers, duties, and authorities delegated to it under the Supplemental Plan to such person or persons, office or committee as it shall select. For the purposes of ERISA, the Company shall be the Plan sponsor and the Plan Administrator.

(c) Whenever there is denied, whether in whole or in part, a claim for benefits under the Supplemental Plan filed by any person (herein referred to as the “Claimant”), the Plan Administrator shall transmit a written notice of such decision to the Claimant within 90 days of receiving the claim from the Claimant, which notice shall be written in a manner calculated to be understood by the Claimant and shall contain a statement of the specific reasons for the denial of the claim, a reference to the relevant Supplemental Plan provisions, a description and explanation of additional information needed, and a statement advising the Claimant that, within 60 days of the date on which he or she receives such notice, he or she may obtain review of such decision in accordance with the procedures hereinafter set forth. Within such 60-day period, the Claimant or the Claimant’s authorized representative may request that the claim denial be reviewed by filing with the Plan Administrator a written request therefor, which request shall contain the following information:

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Within 60 days of the date determined pursuant to clause (i) above, the Plan Administrator shall conduct a full and fair review of the decision denying the Claimant’s claim for benefits. Within 60 days of the date of such hearing, the Plan Administrator shall render its written decision on review, written in a manner calculated to be understood by the Claimant and including the reasons and Plan provisions upon which its decision was based, a statement that the Claimant is entitled to receive, upon request and free of charge, reasonable access to and copies of all documents and other information relevant to the claim, and a statement describing the Claimant’s right to bring an action under Section 502(a) of ERISA.

(a) The Company has reserved and does hereby reserve the right to amend, restate or terminate, at any time, any or all of the provisions of the Supplemental Plan,

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without the consent of any Participant, Spouse, beneficiary, or any other person. Without limiting the authority of the Board of Directors of the Company or a duly authorized committee thereof to amend, restate or terminate the Supplemental Plan, the Board of Directors of the Company has authorized and instructed its Executive Vice President - Human Resources and Organizational Advancement (or any other officer or delegate of an officer) to amend, restate or terminate the Plan. Any amendment, restatement or termination of the Plan shall be expressed in an instrument executed in the name of the Company. Any such amendment, restatement or termination shall become effective as of the date designated in such instrument or, if no such date is specified, on the date of its execution.

(b) Notwithstanding paragraph 9(a) hereof, no amendment, restatement or termination of the Supplemental Plan shall, without the consent of the Participant (or, in the case of his or her death, his or her beneficiary or Spouse, as applicable), adversely affect (i) the benefit under the Supplemental Plan of any Participant, Spouse or beneficiary then entitled to receive a benefit under the Supplemental Plan or (ii) the right of any Participant to receive upon termination of employment with the Company (or the right of the Participant’s Spouse or other beneficiary, as applicable, to receive upon the Participant’s death) that benefit which would have been received under the Supplemental Plan if such employment of the Participant had terminated immediately prior to the amendment, restatement or termination of the Supplemental Plan; provided, however, that the consent requirement of Participants, Spouses or other beneficiaries to certain actions shall not apply to any amendment or termination made by the Company pursuant to paragraph 11(b). Notwithstanding any provision to the contrary, the Company, in its sole discretion, may terminate this Supplemental Plan in accordance with Treasury Regulation Section 1.409A-3(j)(4)(ix), or any successor provision.

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For a period of two years following a Participant’s separation from service, the Participant shall not (a) engage or participate, directly or indirectly, in any Competitive Activity (as defined below), or (b) solicit or cause to be solicited on behalf of a competitor any person or entity which was a customer of the Company during the three year period ending on the Participant’s retirement date, if the Participant had any direct responsibility for such customer while employed by the Company. The term “Competitive Activity” shall mean the Participant’s participation, without the written consent of an officer of the Company, in the management of any business enterprise if such enterprise engages in substantial and direct competition with the Company and such enterprise’s sales of any product or service competitive with any product or service of the Company amounted to 25% of such enterprise’s net sales for its most recently completed fiscal year and if the Company’s net sales of said product or service amounted to 25% of the Company’s net sales for its most recently completed fiscal year. “Competitive Activity” shall not include (y) the mere ownership of securities in any enterprise and exercise of rights appurtenant thereto or (z) participation in management of any enterprise or business operation thereof other than in connection with the competitive operation of such enterprise. If a Participant engages in activity prohibited by this paragraph, then in addition to all other remedies available to the Company, the Company shall be released of any obligation under the Supplemental Plan to pay benefits to such Participant or to such Participant’s Spouse or beneficiary under the Supplemental Plan.

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(a) To the extent applicable, it is intended that this Supplemental Plan (including all amendments thereto) comply with the provisions of Section 409A of the Code, so that the income inclusion provisions of Section 409A(a)(1) of the Code do not apply to the Participant, Spouse or a beneficiary. This Supplemental Plan shall be administered in a manner consistent with this intent.

(b) Notwithstanding any provision of this Supplemental Plan to the contrary, in light of the uncertainty with respect to the proper application of Section 409A of the Code, the Company reserves the right to make amendments to this Supplemental Plan as the Company deems necessary or desirable to avoid the imposition of taxes or penalties under Section 409A of the Code. In any case, a Participant shall be solely responsible and liable for the satisfaction of all taxes and penalties that may be imposed on a Participant or for a Participant’s account in connection with this Supplemental Plan (including any taxes and penalties under Section 409A of the Code), and neither the Company nor any of its affiliates shall have any obligation to indemnify or otherwise hold a Participant harmless from any or all of such taxes or penalties.

IN WITNESS WHEREOF, the Company has caused this Plan to be executed by a duly authorized officer at Canton, Ohio, this     day of             , 2014.

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