The Annual Meeting of Stockholders of HF Sinclair Corporation will be held on Wednesday, May 24, 2023, at 8:30 a.m. CDT, in a virtual meeting format only. Stockholders of record will be able to vote and ask questions online during the meeting. If you would like to attend the virtual meeting and have your 16-digit control number included on your proxy card, please go to www.virtualshareholdermeeting.com/DINO2023 15 minutes before the start of the meeting to log in. Stockholders who do not have a control number may gain access to the meeting by logging into their brokerage firm’s website and selecting the stockholder communications mailbox to link through to the meeting.