PARENT GUARANTY

Exhibit 4.5

PARENT GUARANTY

THIS GUARANTY (this “Guaranty”) dated as of November 25, 2013 is made by UNITED STATIONERS INC., a Delaware corporation (the “Guarantor”), in favor of the holders from time to time of the Notes hereinafter referred to, including each purchaser named in the Note Purchase Agreement hereinafter referred to, and their respective successors and assigns (collectively, the “Holders” and each individually, a “Holder”).

WITNESSETH:

WHEREAS, UNITED STATIONERS SUPPLY CO., an Illinois corporation (the “Company”), the Guarantor and the initial Holders have entered into a Note Purchase Agreement dated as of November 25, 2013 (the Note Purchase Agreement as amended, supplemented, restated or otherwise modified from time to time in accordance with its terms and in effect, the “Note Purchase Agreement”);

WHEREAS, the Note Purchase Agreement contemplates the issuance by the Company of Notes (as defined in the Note Purchase Agreement);

WHEREAS, the Company is a wholly owned Subsidiary of the Guarantor and the Guarantor will derive substantial benefits from the purchase by the Holders of the Notes;

WHEREAS, it is a condition precedent to the obligation of the Holders to purchase the Notes that the Guarantor shall have executed and delivered this Guaranty to the Holders; and

WHEREAS, the Guarantor desires to execute and deliver this Guaranty to satisfy the conditions described in the preceding paragraph;

NOW, THEREFORE, in consideration of the premises and other benefits to the Guarantor, and of the purchase of the Notes by the Holders, and for other good and valuable consideration, the receipt and sufficiency of which are acknowledged, the Guarantor makes this Guaranty as follows:

SECTION 1. DEFINITIONS.

Any capitalized terms not otherwise herein defined shall have the meanings ascribed to them in the Note Purchase Agreement.

SECTION 2. GUARANTY.

The Guarantor unconditionally and irrevocably guarantees to the Holders the due, prompt and complete payment by the Company of the principal of, Make-Whole Amount and interest on (including interest accruing or becoming owing subsequent to the commencement of any bankruptcy, reorganization or similar proceeding involving the Company), and each other amount due under, the Notes and the Note Purchase Agreement, when and as the same shall

become due and payable (whether at stated maturity or by required or optional prepayment or by declaration or otherwise) in accordance with the terms of the Notes and the Note Purchase Agreement (the Notes and the Note Purchase Agreement being sometimes hereinafter collectively referred to as the “Note Documents” and the amounts payable by the Company under the Note Documents, and all other monetary obligations of the Company thereunder (including any reasonable attorneys’ fees and expenses), being sometimes collectively hereinafter referred to as the “Obligations”). This Guaranty is a guaranty of payment and not just of collectibility and is in no way conditioned or contingent upon any attempt to collect from the Company or upon any other event, contingency or circumstance whatsoever. If for any reason whatsoever the Company shall fail or be unable duly, punctually and fully to pay such amounts as and when the same shall become due and payable, the Guarantor, without demand, presentment, protest or notice of any kind, will forthwith pay or cause to be paid such amounts to the Holders under the terms of such Note Documents, in lawful money of the United States, at the place specified in the Note Purchase Agreement, or perform or comply with the same or cause the same to be performed or complied with, together with interest (to the extent provided for under such Note Documents) on any amount due and owing from the Company. The Guarantor, promptly after demand, will pay to the Holders the reasonable costs and expenses of collecting such amounts or otherwise enforcing this Guaranty, including, without limitation, the reasonable fees and expenses of counsel.

SECTION 3. GUARANTOR’S OBLIGATIONS UNCONDITIONAL.

The obligations of the Guarantor under this Guaranty shall be primary, absolute and unconditional obligations of the Guarantor, shall not be subject to any counterclaim, set-off, deduction, diminution, abatement, recoupment, suspension, deferment, reduction or defense based upon any claim the Guarantor or any other person may have against the Company or any other person, and to the full extent permitted by applicable law shall remain in full force and effect without regard to, and shall not be released, discharged or in any way affected by, any circumstance or condition whatsoever other than the indefeasible payment in full of the Obligations (whether or not the Guarantor or the Company shall have any knowledge or notice thereof), including:

(a) any termination, amendment or modification of or deletion from or addition or supplement to or other change in any of the Note Documents or any other instrument or agreement applicable to any of the parties to any of the Note Documents;

(b) any furnishing or acceptance of any security, or any release of any security, for the Obligations, or the failure of any security or the failure of any person to perfect any interest in any collateral;

(c) any failure, omission or delay on the part of the Company to conform or comply with any term of any of the Note Documents or any other instrument or agreement referred to in paragraph (a) above, including, without limitation, failure to give notice to the Guarantor of the occurrence of a “Default” or an “Event of Default” under any Note Document;

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(d) any waiver of the payment, performance or observance of any of the obligations, conditions, covenants or agreements contained in any Note Document, or any other waiver, consent, extension, indulgence, compromise, settlement, release or other action or inaction under or in respect of any of the Note Documents or any other instrument or agreement referred to in paragraph (a) above or any obligation or liability of the Company, or any exercise or non-exercise of any right, remedy, power or privilege under or in respect of any such instrument or agreement or any such obligation or liability;

(e) any failure, omission or delay on the part of any of the Holders to enforce, assert or exercise any right, power or remedy conferred on such Holder in this Guaranty, or any such failure, omission or delay on the part of such Holder in connection with any Note Document, or any other action on the part of such Holder;

(f) any voluntary or involuntary bankruptcy, insolvency, reorganization, arrangement, readjustment, assignment for the benefit of creditors, composition, receivership, conservatorship, custodianship, liquidation, marshaling of assets and liabilities or similar proceedings with respect to the Company, the Guarantor or to any other person or any of their respective properties or creditors, or any action taken by any trustee or receiver or by any court in any such proceeding;

(g) any discharge, termination, cancellation, frustration, irregularity, invalidity or unenforceability, in whole or in part, of any of the Note Documents or any other agreement or instrument referred to in paragraph (a) above or any term hereof;

(h) any merger or consolidation of the Company or the Guarantor into or with any other corporation, or any sale, lease or transfer of any of the assets of the Company or the Guarantor to any other person;

(i) any change in the ownership of any shares of capital stock of the Company or any change in the corporate relationship between the Company and the Guarantor, or any termination of such relationship;

(j) any release or discharge, by operation of law, of any other guarantor from the performance or observance of any obligation, covenant or agreement contained in any other guarantee of the Note Documents or the Obligations; or

(k) any other occurrence, circumstance, happening or event whatsoever, whether similar or dissimilar to the foregoing, whether foreseen or unforeseen, and any other circumstance which might otherwise constitute a legal or equitable defense or discharge of the liabilities of a guarantor or surety or which might otherwise limit recourse against the Guarantor.

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SECTION 4. FULL RECOURSE OBLIGATIONS.

The obligations of the Guarantor set forth herein constitute the full recourse obligations of the Guarantor enforceable against it to the full extent of all its assets and properties.

SECTION 5. WAIVER.

The Guarantor unconditionally waives, to the extent permitted by applicable law, (a) notice of any of the matters referred to in Section 3, (b) notice to the Guarantor of the incurrence of any of the Obligations, notice to the Guarantor or the Company of any breach or default by the Company with respect to any of the Obligations or any other notice that may be required, by statute, rule of law or otherwise, to preserve any rights of the Holders against the Guarantor, (c) presentment to or demand of payment from the Company or the Guarantor with respect to any amount due under any Note Document or protest for nonpayment or dishonor, (d) any right to the enforcement, assertion or exercise by any of the Holders of any right, power, privilege or remedy conferred in the Note Purchase Agreement or any other Note Document or otherwise, (e) any requirement of diligence on the part of any of the Holders, (f) any requirement to exhaust any remedies or to mitigate the damages resulting from any default under any Note Document, (g) any notice of any sale, transfer or other disposition by any of the Holders of any right, title to or interest in the Note Purchase Agreement or in any other Note Document and (h) any other circumstance whatsoever which might otherwise constitute a legal or equitable discharge, release or defense of a guarantor or surety or which might otherwise limit recourse against the Guarantor.

SECTION 6. SUBROGATION, CONTRIBUTION, REIMBURSEMENT OR INDEMNITY.

Until all Obligations have been indefeasibly paid in full, the Guarantor agrees not to take any action pursuant to any rights which may have arisen in connection with this Guaranty to be subrogated to any of the rights (whether contractual, under the United States Bankruptcy Code, as amended, including section 509 thereof, under common law or otherwise) of any of the Holders against the Company or against any collateral security or guaranty or right of offset held by the Holders for the payment of the Obligations. Until all Obligations have been indefeasibly paid in full, the Guarantor agrees not to take any action pursuant to any contractual, common law, statutory or other rights of reimbursement, contribution, exoneration or indemnity (or any similar right) from or against the Company which may have arisen in connection with this Guaranty. So long as the Obligations remain, if any amount shall be paid by or on behalf of the Company to the Guarantor on account of any of the rights waived in this paragraph, such amount shall be held by the Guarantor in trust, segregated from other funds of the Guarantor, and shall, forthwith upon receipt by the Guarantor, be turned over to the Holders (duly endorsed by the Guarantor to the Holders, if required), to be applied against the Obligations, whether matured or unmatured, in such order as the Holders may determine.

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SECTION 7. EFFECT OF BANKRUPTCY PROCEEDINGS, ETC.

This Guaranty shall continue to be effective or be automatically reinstated, as the case may be, if at any time payment, in whole or in part, of any of the sums due to any of the Holders pursuant to the terms of the Note Purchase Agreement or any other Note Document is rescinded or must otherwise be restored or returned by the Holder upon the insolvency, bankruptcy, dissolution, liquidation or reorganization of the Company or any other person, or upon or as a result of the appointment of a custodian, receiver, trustee or other officer with similar powers with respect to the Company or other person or any substantial part of its property, or otherwise, all as though such payment had not been made. If an event permitting the acceleration of the maturity of the principal amount of the Notes shall at any time have occurred and be continuing and one or more Holders shall have attempted to accelerate the maturity of the principal amount of the Notes pursuant to and in compliance with Section 12.1 of the Note Purchase Agreement, or an event shall have occurred that pursuant to Section 12.1 of the Note Purchase Agreement purportedly results in the automatic acceleration of the maturity of the principal amount of the Notes, and in either such case such acceleration shall at such time be prevented by reason of the pendency against the Company or any other Person of a case or proceeding under a bankruptcy or insolvency law, the Guarantor agrees that, for purposes of this Guaranty and its obligations hereunder, the maturity of the principal amount of the Notes and all other Obligations shall be deemed to have been accelerated with the same effect as if any Holder had accelerated the same in accordance with the terms of the Note Purchase Agreement or other applicable Note Document, and the Guarantor shall forthwith pay such principal amount, Make-Whole Amount, if any, and interest thereon and any other amounts guaranteed hereunder without further notice or demand.

SECTION 8. TERM OF AGREEMENT.

This Guaranty and all guaranties, covenants and agreements of the Guarantor contained herein shall continue in full force and effect and shall not be discharged until such time as all of the Obligations shall be paid and performed in full and all of the agreements of the Guarantor hereunder shall be duly paid and performed in full.

SECTION 9. NOTICES.

All notices and communications provided for hereunder shall be in writing and sent by telecopy if the sender on the same day sends a confirming copy of such notice by a recognized overnight delivery service (charges prepaid), or by registered or certified mail with return receipt requested (postage prepaid), or by a recognized overnight delivery service (with charges prepaid) (a) if to the Company or any Holder at the address set forth in the Note Purchase Agreement or (b) if to the Guarantor, in care of the Company at the Company’s address set forth in the Note Purchase Agreement, or in each case at such other address as the Company, any Holder or such Guarantor shall from time to time designate in writing to the other parties. Any notice so addressed shall be deemed to be given when actually received.

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SECTION 10. SURVIVAL.

All warranties, representations and covenants made by the Guarantor herein or in any certificate or other instrument delivered by it or on its behalf hereunder shall be considered to have been relied upon by the Holders and shall survive the execution and delivery of this Guaranty, regardless of any investigation made by any of the Holders. All statements in any such certificate or other instrument shall constitute warranties and representations by such Guarantor hereunder.

SECTION 11. JURISDICTION AND PROCESS; WAIVER OF JURY TRIAL.

(a) The Guarantor irrevocably submits to the non-exclusive jurisdiction of any New York state or federal court sitting in the Borough of Manhattan, The City of New York, over any suit, action or proceeding arising out of or relating to this Parent Guaranty, the Note Purchase Agreement or the Notes. To the fullest extent permitted by applicable law, the Guarantor irrevocably waives and agrees not to assert, by way of motion, as a defense or otherwise, any claim that it is not subject to the jurisdiction of any such court, any objection that it may now or hereafter have to the laying of the venue of any such suit, action or proceeding brought in any such court and any claim that any such suit, action or proceeding brought in any such court has been brought in an inconvenient forum.

(b) The Guarantor consents to process being served by or on behalf of any holder of Notes in any suit, action or proceeding solely of the nature referred to in Section 11(a) by mailing a copy thereof by registered, certified or priority mail, postage prepaid, return receipt requested, or delivering a copy thereof in the manner for delivery of notices specified in Section 9, to it. The Guarantor agrees that such service upon receipt (i) shall be deemed in every respect effective service of process upon it in any such suit, action or proceeding and (ii) shall, to the fullest extent permitted by applicable law, be taken and held to be valid personal service upon and personal delivery to it. Notices hereunder shall be conclusively presumed received as evidenced by a delivery receipt furnished by the United States Postal Service or any reputable commercial delivery service.

(c) Nothing in this Section 11 shall affect the right of any holder of a Note to serve process in any manner permitted by law, or limit any right that the holders of any of the Notes may have to bring proceedings against the Guarantor in the courts of any appropriate jurisdiction or to enforce in any lawful manner a judgment obtained in one jurisdiction in any other jurisdiction.

(d) The Guarantor waives trial by jury in any action brought on or with respect to this Agreement, the notes or any other document executed in connection herewith or therewith.

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SECTION 12. MISCELLANEOUS.

Any provision of this Guaranty that is prohibited or unenforceable in any jurisdiction shall, as to such jurisdiction, be ineffective to the extent of such prohibition or unenforceability without invalidating the remaining provisions hereof, and any such prohibition or unenforceability in any jurisdiction shall not invalidate or render unenforceable such provision in any other jurisdiction. To the extent permitted by applicable law, the Guarantor hereby waives any provision of law that renders any provisions hereof prohibited or unenforceable in any respect. The terms of this Guaranty shall be binding upon, and inure to the benefit of, the Guarantor and the Holders and their respective successors and assigns. No term or provision of this Guaranty may be changed, waived, discharged or terminated orally, but only by an instrument in writing signed by the Guarantor and the Required Holders. The section and paragraph headings in this Guaranty are for convenience of reference only and shall not modify, define, expand or limit any of the terms or provisions hereof, and all references herein to numbered sections, unless otherwise indicated, are to sections in this Guaranty. This Guaranty shall in all respects be governed by, and construed in accordance with, the laws of the State of New York excluding choice-of-law principles of the law of such State that would require the application of the laws of a jurisdiction other than such State.

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IN WITNESS WHEREOF, the Guarantor has caused this Guaranty to be duly executed as of the day and year first above written.