Issue of shares pursuant to convertible bonds

3 June 2019

Sirius Minerals Plc

Issue of shares pursuant to convertible bonds

Sirius Minerals Plc ("Sirius" or the "Company") announces that it has received four conversion notices in respect of the US$106.6 million Guaranteed Convertible Bonds due 2027 (ISIN: XS XS1991118255) ("Non-Escrow Bonds") which were issued by Sirius Minerals Finance No.2 Limited, and guaranteed by the Company, in connection with the Company's Stage 2 financing and announced on 30 April 2019 (RNS number 5209X) and 1 May 2019 (RNS number 7014X), pursuant to which it will allot and issue 17,191,975 new ordinary shares of 0.25 pence each (the "Relevant Shares").

An application has been made for the Relevant Shares to be admitted to the premium listing segment of the Official List of the Financial Conduct Authority (the "FCA") and to trading on the London Stock Exchange plc's main market for listed securities, and dealings are expected to commence at 8.00 am on 6 June 2019. The Relevant Shares will rank pari passu in all respects with all existing ordinary shares in the Company.

In accordance with the requirements of the FCA's Disclosure Guidance and Transparency Rules 5.6.1AR and 5.6.2G, the Company confirms that the enlarged share capital of the Company following Admission will be 6,994,729,804 Ordinary Shares in aggregate, each with equal voting rights. No shares are held in treasury. The above figure may be used by shareholders (and others with notification obligations) as the denominator for the calculations by which they will determine if they are required to notify their interest in, or a change to their interest in, Sirius Minerals Plc under the FCA's Disclosure Guidance and Transparency Rules.

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About Sirius Minerals Plc

Sirius Minerals Plc is focused on the development of the Woodsmith Mine, which will access the world's largest and highest grade polyhalite deposit located in North Yorkshire, United Kingdom. The Company's polyhalite product, POLY4, is a unique multi-nutrient fertilizer, which can be used to increase balanced fertilization around the world. Sirius Minerals' shares are traded on the Premium List of the London Stock Exchange. Its shares are also traded in the United States on the OTCQX through a sponsored ADR facility. Further information on the Company can be found at: www.siriusminerals.com.