Exhibit 99.1 Metallus Announces Fourth-Quarter and Full-Year 2023 Results • Net sales of $328.1 million in the fourth quarter and $1.4 billion for the full year • Fourth-quarter net income of $1.3 million and full-year net income of $69.4 million with adjusted EBITDA (1) of $35.7 million in the fourth quarter and $169.0 million for the full year • Operating cash flow of $74.1 million in the fourth quarter with $125.3 million for the full year • For the full year, the company deployed $51.6 million of cash f ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 10-Q ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended September 30, 2023 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission file number: 1-36313 TIMKENSTEEL CORPORATION (Exact name of registrant as specified in its charter) Ohio 46-4024951 (State or other jurisdiction of inc ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 10-Q ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2023 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission file number: 1-36313 TIMKENSTEEL CORPORATION (Exact name of registrant as specified in its charter) Ohio 46-4024951 (State or other jurisdiction of incorpor ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 10-Q ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2023 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission file number: 1-36313 TIMKENSTEEL CORPORATION (Exact name of registrant as specified in its charter) Ohio 46-4024951 (State or other jurisdiction of incorpo ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 10-K ☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2022 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to . Commission file number: 1-36313 TIMKENSTEEL CORPORATION (Exact name of registrant as specified in its charter) Ohio 46-4024951 (State or other jurisdiction of incorporat ...