Based on 20 Glassdoor salary reports at Mars, Shift Managers typically earn $50K - $85K in total pay nationally. Base pay comes in around $46K - $77K, with bonus pay adding roughly $4K - $7K.
I also found 24 Glassdoor job listings for shift manager-related roles tied to Mars. You can narrow those down by pay, company, or remote/on-site status.