Originally, the name was spelled "Saint Mary's Hospital", as can be seen in stone above the old front entrance, but in recent years the apostrophe is usually omitted.

[9][10] The Mayo Clinic Hospital – Rochester, Saint Marys Campus has 1,265 licensed beds and 64 operating rooms.

Saint Marys Hospital Emergency Department provides care for approximately 80,000 patients per year, serving the local population (constituting about 85% of patients) and being a referral for southern and central Minnesota, northern Iowa and western Wisconsin through Mayo One medical helicopter service.

St Marys also has a multiple dedicated trauma/surgical ICU's and hybrid operating rooms to provide the highest level of trauma care for the surrounding community.

[18] The Mayo Clinic Hospital – Rochester, Methodist Campus has 794 licensed beds and 51 operating rooms.

This year U.S. News expanded their common procedures and conditions list to 9 individual measures, and Mayo was one of fewer than 70 hospitals to score High Performing in every category.