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UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington , D.C. 20549 X ANNUAL REPORT PURSUANT TO SECTION 13 OR 15 ( d ) OF THE SECURITIES EXCHANGE ACT OF 1934 FORM 10 - K For the Fiscal Year Ended December 31 , 2020 OR TRANSITION REPORT PURSUANT TO SECTION 13 OR 15 ( d ) OF THE SECURITIES EXCHANGE ACT OF 1934 Delaware ( State or other jurisdiction of Incorporation or Organization ) US SILICAⓇ U.S. Silica Holdings , Inc. ( Exact name of registrant as specified in its charter ) Title of each class : Common Stock , par value $ 0.01 per share Commission file number 001-35416 24275 Katy Freeway , Suite 600 Katy , Texas 77494 ( Address of Principal Executive Offices ) ( Zip Code ) ( 281 ) 258-2170 ( Registrant's telephone number , including area code ) Securities registered pursuant to Section 12 ( b ) of the Securities Act : Trading Symbol : 26-3718801 ( I.R.S. Employer Identification No. ) SLCA Name of each exchange on which registered : New York Stock Exchange Securities registered pursuant to Section 12 ( g ) of the Securities Act : None No p Indicate by a check mark if the registrant is a well - known seasoned issuer , as defined in Rule 405 of the Securities Act . Yes ¨ Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15 ( d ) of the Act . Yes Indicate by check mark whether the registrant ( 1 ) has filed all reports required to be filed by Section 13 or 15 ( d ) of the Securities Exchange Act of 1934 during the preceding 12 months ( or for such shorter period that the registrant was required to file such reports ) , and ( 2 ) has been subject to such filing requirements for the past 90 days . Yes þ No " ** No p Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S - T ( §232.405 of this chapter ) during the preceding 12 months ( or for such shorter period that the registrant was required to submit such files ) . Yes p No " Indicate by check mark whether the registrant is a large accelerated filer , an accelerated filer , a non - accelerated filer , a smaller reporting company , or an emerging growth company . See the definitions of " large accelerated filer , " " accelerated filer , ” “ smaller reporting company , " and " emerging growth company " in Rule 12b - 2 of the Exchange Act .