Three Sisters of Mercy from Dublin, Ireland arrived in St. John’s, Newfoundland on June 3, 1842, establishing the first convent of Mercy in the Americas.

Today Sisters of Mercy of Newfoundland make a commitment to alleviate injustice and to reach out in compassion and service to the poor and oppressed, especially to women.

In 2001 the Mercy Centre for Ecology and Justice was established in St. John’s. This office highlights the congregation's commitment ‘to focus our resources and energy towards examining, challenging and healing injustice and oppression’ and ‘to live a spirituality flowing from a sense of the sacredness of creation.’

The Gathering Place, a Centre for Poor and Vulnerable People, was founded in 1994 as a joint initiative of Sisters of Mercy and Presentation Sisters. The Gathering Place is a Service Centre committed to building community, promoting equality and providing nourishment for those seeking respite from isolation and loneliness.

Many of the sisters commit themselves on a regular basis to setting up, managing or volunteering their time in food banks. Others provide for the religious, spiritual, and physical care of the sick and aged at home and in hospitals, in personal care homes and nursing homes. The congregation administers a long-term care facility for the aged in St. John’s: St. Patrick’s Mercy Home. Some sisters have been active in ministry with the Aboriginal People in the Mi'kmaq in Conne River on the island of Newfoundland and the Innu in Sheshatshiu in Labrador.

Additional ministries include: working in the prison system as advocates, teachers, and pastoral care-givers; ministering as spiritual directors and spiritual facilitators; teaching in catechetical programs; counseling in formal settings such as hospitals, mental health programs, prison and counseling centres; and working with immigrants and refugees in resettlement programmes. The Sisters of Mercy in Newfoundland have also been noted for bringing the gift of music and song into the lives of many. Though not currently employed as music teachers or directors, sisters continue to share their musical talents in the parishes or other facilities where they minister.