Sinclair Oil (Sinclair), an HF Sinclair (NYSE: DINO) brand, announced today the national launch of Mammoth Monday™, a new weekly fuel savings event designed to reward loyal customers with one of Sinclair’s biggest fuel discounts of the week. Beginning Monday, Aug. 3, 2026, eligible DINOPAY® users can activate an exclusive in-app coupon and save 20 cents per gallon—or 25 cents per gallon with Mobile Advantage™—every Monday at participating Sinclair stations.
Available exclusively through the DINOPAY mobile app, Mammoth Monday gives eligible customers an extra discount every Monday at participating Sinclair locations. Customers simply activate the coupon before fueling to receive the offer, with enhanced savings available through Mobile Advantage when using an eligible linked bank account.
“At Sinclair, we’re always looking for new ways to deliver meaningful value to our customers,” said Fergie Theriault, vice president, Marketing. “We’re excited to bring this weekly savings opportunity to drivers across the country. Whether you’re commuting to work, heading out on the road or simply filling up for the week ahead, Mondays are now the best day to fuel at Sinclair.”
Mammoth Monday is designed to encourage members to make Sinclair their weekly fueling destination while introducing more drivers to the convenience and benefits of DINOPAY. In addition to exclusive fuel discounts, the app allows users to securely pay for fuel and eligible in-store purchases, access digital receipts, locate nearby Sinclair stations and receive additional offers throughout the year.
Customers can participate by:
- Downloading the free DINOPAY app from the App Store® or Google Play™.
- Enrolling in DINOPAY and linking an eligible payment method.
- Activating the Mammoth Monday in-app coupon in DINOPAY before fueling, then using an eligible linked payment method at a participating Sinclair station every Monday to receive the applicable discount.
For more information or to download DINOPAY, visit https://www.sinclairoil.com/dinopay. For complete offer terms, eligibility requirements, participating locations and applicable gallon limits, visit https://www.sinclairoil.com/dinopay-offers. Terms and conditions apply. App Store® is a registered trademark of Apple Inc. Google Play™ is a trademark of Google LLC.
About HF Sinclair Corporation:
HF Sinclair Corporation, headquartered in Dallas, Texas, is an independent energy company that produces and markets high-value light products such as gasoline, diesel fuel, jet fuel, renewable diesel and other specialty products. HF Sinclair owns and operates refineries in Kansas, Oklahoma, New Mexico, Wyoming, Washington and Utah. HF Sinclair provides petroleum products and crude oil transportation, terminaling, storage and throughput services to its refineries and the petroleum industry. HF Sinclair markets its refined products principally in the Southwest U.S., the Rocky Mountains extending into the Pacific Northwest and in other neighboring Plains states. It supplies high-quality fuels to more than 1,800 branded stations and licenses the use of the Sinclair brand to more than 350 additional locations throughout the country. HF Sinclair produces renewable diesel at two of its facilities in Wyoming and also at its facility in Artesia, New Mexico. In addition, we produce and market base oils and other specialized lubricants in the U.S., Canada and the Netherlands, and export products to more than 80 countries.
About Sinclair Oil:
Sinclair Oil, an HF Sinclair brand, is one of the oldest continuous brands in the energy business. Recognized for its iconic dinosaur, Sinclair has more than 1,800 independent Sinclair-branded and licensed stations throughout the country. DINOPAY® is an app-based payment system that allows users to pay for fuel and in-store items with their mobile device, track receipts, utilize fuel discounts and locate the nearest Sinclair location.
View source version on businesswire.com: https://www.businesswire.com/news/home/20260804771170/en/
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