UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of the Securities

Exchange Act of 1934 (Amendment No.)

Filed by the Registrant ☒

Filed by a Party other than the Registrant ☐

Check the appropriate box:

☐ Preliminary Proxy Statement

☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2))

☐ Definitive Proxy Statement

☒ Definitive Additional Materials

☐ Soliciting Material Pursuant to §240.14a-12

ALPHATEC HOLDINGS, INC.

(Name of Registrant as Specified In Its Charter)

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

Payment of Filing Fee (Check all boxes that apply):

☒ No fee required

☐ Fee paid previously with preliminary materials

☐ Fee computed on table in exhibit required by Item 25(b) per Exchange Act Rules 14a-6(i)(1) and 0-11

Alphatec Holdings, Inc. Important Notice Regarding the Availability of Proxy Materials Stockholders Meeting to be held on June 15, 2022 For Stockholders of record as of April 19, 2022 Have the 12 digit control number located in the shaded box above available when you access the website and follow the instructions. When requesting via the Internet or telephone you will need the 12 digit control number located in the shaded box above. * If requesting material by e-mail, please send a blank e-mail with the 12 digit control number (located above) in the subject line. No other requests, instructions OR other inquiries should be included with your e-mail requesting material. Alphatec Holdings, Inc. Meeting Type: Date: Time: Place: Annual Meeting of Stockholders Wednesday, June 15, 2022 10:00 AM, Pacific Time 1950 Camino Vida Roble, Carlsbad, CA 92008 SEE REVERSE FOR FULL AGENDA INTERNET www.investorelections.com/ATEC TELEPHONE (866) 648-8133 * E-MAIL paper@investorelections.com To order paper materials, use one of the following methods. For a convenient way to view proxy materials and VOTE go to www.proxydocs.com/ATEC If you want to receive a paper or e-mail copy of the proxy material, you must request one. There is no charge to you for requesting a copy. In order to receive a paper package in time for this year's meeting, you must make this request on or before June 03, 2022. This communication presents only an overview of the more complete proxy materials that are available to you on the Internet. This is not a ballot. You cannot use this notice to vote your shares. We encourage you to access and review all of the important information contained in the proxy materials before voting. To view the proxy materials, and to obtain directions to attend the meeting, go to: www.proxydocs.com/ATEC To vote your proxy while visiting this site, you will need the 12 digit control number in the box below. Under United States Securities and Exchange Commission rules, proxy materials do not have to be delivered in paper. Proxy materials can be distributed by making them available on the internet. P.O. BOX 8016, CARY, NC 27512-9903 (Company Logo)

Alphatec Holdings, Inc. Annual Meeting of Stockholders PROPOSAL 1. Election of Directors 1.01 Elizabeth Altman 1.02 Evan Bakst 1.03 Andy S. Barnett 1.04 Mortimer Berkowitz III 1.05 Quentin Blackford 1.06 Karen K. McGinnis 1.07 Marie Meynadier 1.08 Patrick S. Miles 1.09 David H. Mowry 1.10 David Pelizzon 1.11 Jeffrey P. Rydin 1.12 James L.L. Tullis 1.13 Ward W. Woods 2. To ratify the selection of Deloitte & Touche LLP as the Company’s independent registered public accounting firm for the fiscal year ending December 31, 2022; 3. To approve, on an advisory basis, the compensation of the Company’s named executive officers. THE BOARD OF DIRECTORS RECOMMENDS A VOTE: FOR ON PROPOSALS 1, 2 AND 3