Sierra Metals Announces Filing of NI 43-101 Technical Report for Significantly Increased Mineral Resource Estimate for Cusi Silver Mine, Mexico

Sierra Metals Inc. (TSX: SMT) (BVL: SMT) (NYSE AMERICAN: SMTS) ("Sierra Metals" or "the Company") has filed an independent technical report (the "Report ") prepared in accordance with National Instrument 43-101 ("NI 43-101") on the Cusi Mine in Mexico.

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The Report dated November 13, 2020, with an effective date of August 31, 2020, is entitled "Independent Technical Report for the Cusi Mine, Chihuahua State, Mexico." The Report was prepared for Sierra Metals by SRK Consulting (Canada) Inc. There are no material differences in the Report from those results disclosed in the Company's press release dated November 18, 2020.

The Report is available for review on SEDAR (www.sedar.com), EDGAR (www.SEC.gov), and the Company's website (www.sierrametals.com).

Highlights of the technical report filed include:

• Total Measured and Indicated Resources increased 18% to 5,356,000 tonnes from 4,557,000 tonnes previously reported; and Total Inferred Resources increased 200% to 4,893,000 tonnes from 1,633,000 tonnes previously reported
• Total Measured Mineral Resources for Cusi are 850,000 tonnes averaging 213 g/t silver, 0.06 g/t gold, 0.26% lead and 0.30% zinc, and 231 g/t silver equivalent
• Total Indicated Mineral Resources for Cusi are 4,506,000 tonnes averaging 176 g/t silver, 0.13 g/t gold, 0.54% lead, 0.63% zinc and 212 g/t silver equivalent
• Total Inferred Mineral Resources for Cusi are 4,893,000 tonnes averaging 146 g/t silver, 0.18 g/t gold, 0.43% lead, 0.69% zinc and 183 g/t silver equivalent
• The updated Resource Estimate has incorporated new exploration drilling, sampling, and underground mapping information into the geologic interpretation and grade estimations, thereby providing more refined resource models in the Santa Rosa de Lima and Northeast-Southwest zones

Signed by Qualified Persons:

Giovanny Ortiz, B.Sc., PGeo., SRK Principal Consultant (Resource Geology)
Carl Kottmeier, B.A.Sc., P. Eng., MBA, SRK Principal Consultant (Mining)
Daniel H. Sepulveda, BSc, SME-RM, SRK Associate Consultant (Metallurgy)

Quality Control

All technical data contained in this news release has been reviewed and approved by:

Americo Zuzunaga, FAusIMM CP (Mining Engineer) and Vice President of Corporate Planning is a Qualified Person under National Instrument 43-101 – Standards of Disclosure for Mineral Projects.

Augusto Chung, FAusIMM CP (Metallurgist) and Vice President of Metallurgy and Projects to Sierra Metals is a Qualified Person under National Instrument 43-101 – Standards of Disclosure for Mineral Projects.

About Sierra Metals

Sierra Metals Inc. is a diversified Canadian mining company focused on the production and development of precious and base metals from its polymetallic Yauricocha Mine in Peru, and Bolivar and Cusi Mines in Mexico. The Company is focused on increasing production volume and growing mineral resources. Sierra Metals has recently had several new key discoveries and still has many more exciting brownfield exploration opportunities at all three Mines in Peru and Mexico that are within close proximity to the existing mines. Additionally, the Company also has large land packages at all three mines with several prospective regional targets providing longer-term exploration upside and mineral resource growth potential.

The Company's Common Shares trade on the Bolsa de Valores de Lima and on the Toronto Stock Exchange under the symbol "SMT" and on the NYSE American Exchange under the symbol "SMTS".

For further information regarding Sierra Metals, please visit www.sierrametals.com.

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Forward-Looking Statements

This press release contains "forward-looking information" and "forward-looking statements" within the meaning of Canadian and U.S. securities laws (collectively, "forward-looking information"). Forward-looking information includes, but is not limited to, statements with respect to the date of the 2020 Shareholders' Meeting and the anticipated filing of the Compensation Disclosure. Any statements that express or involve discussions with respect to predictions, expectations, beliefs, plans, projections, objectives, assumptions or future events or performance (often, but not always, using words or phrases such as "expects", "anticipates", "plans", "projects", "estimates", "assumes", "intends", "strategy", "goals", "objectives", "potential" or variations thereof, or stating that certain actions, events or results "may", "could", "would", "might" or "will" be taken, occur or be achieved, or the negative of any of these terms and similar expressions) are not statements of historical fact and may be forward-looking information.

Forward-looking information is subject to a variety of risks and uncertainties, which could cause actual events or results to differ from those reflected in the forward-looking information, including, without limitation, the risks described under the heading "Risk Factors" in the Company's annual information form dated March 30, 2020 for its fiscal year ended December 31, 2019 and other risks identified in the Company's filings with Canadian securities regulators and the United States Securities and Exchange Commission, which filings are available at www.sedar.com and www.sec.gov, respectively.

The risk factors referred to above are not an exhaustive list of the factors that may affect any of the Company's forward-looking information. Forward-looking information includes statements about the future and is inherently uncertain, and the Company's actual achievements or other future events or conditions may differ materially from those reflected in the forward-looking information due to a variety of risks, uncertainties and other factors. The Company's statements containing forward-looking information are based on the beliefs, expectations and opinions of management on the date the statements are made, and the Company does not assume any obligation to update such forward-looking information if circumstances or management's beliefs, expectations or opinions should change, other than as required by applicable law. For the reasons set forth above, one should not place undue reliance on forward-looking information.

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Mike McAllister
Vice President, Investor Relations
Sierra Metals Inc.
Tel: +1 (416) 366-7777
Email: info@sierrametals.com

Americo Zuzunaga
Vice President of
Corporate Planning
Sierra Metals Inc.
Tel: +1 (416) 366-7777

Luis Marchese
CEO
Sierra Metals Inc.
Tel: +1 (416) 366-7777