The history of the congregation dates back to 1738, when Haddam Neck residents, tired of having to travel across the river to attend religious services, petitioned the Connecticut General Assembly to establish their own ecclesiastical society. They were joined in this petition by the residents of Middle Haddam, a village of East Hampton. In May, 1740, the petition was granted. On September 23, 1740, the First Congregational Church of Middle Haddam was formed. On December 16, 1740, sixteen men and thirteen women owned the church covenant. In 1744, the first church building was erected on Hog Hill about half way between the two communities. This building was later replaced in 1813 by another edifice near Hurd Park. Middle Haddam residents withdrew in 1855 to form their own congregation, the Second Congregational Church of Middle Haddam, while Haddam Neck residents continued to meet in the old Hog Hill Meetinghouse. In 1873, Haddam Neck residents received the funds to build a new building, the present Gothic Revival-style church, in Haddam Neck on a bluff overlooking the Connecticut River, which was built at the foot of School House Hill and dedicated on September 3, 1874. It was built with funds left by Edward Davis Clark with the provision that the church be located near the school building. The builder was A. H. Allen of Portland and the total cost of the building and site was $6,000. The church has had little modification except for the removal of the original pipe organ and installation of a barrier-free access ramp. .
The church parish house was Haddam Neck’s schoolhouse. It was built in 1822 and stood across the street from its present location at the bottom of Schoolhouse Hill Road. It was moved to its present location, next to the congregational church, in 1916. When Haddam closed the school in 1925, the property reverted back to the Sydney Brooks family, whose heirs donated the land and building to the church. Both buildings are listed on the State Register of Historic Places.The schoolhouse was moved to its present location, next to the congregational church, in 1916. The church acquired the house on Schoolhouse Hill Road in 1882 as a parsonage and has rented it since 1941. The Lutheran and Methodist-Episcopal churches united with Haddam Neck Church in 1914 to form the Haddam Neck Federated Church. In 1945, the church voted to change its name to the Haddam Neck Congregational Church. From 1941 to 1969, the church was yoked with the Second Congregational Church of Middle Haddam. In May, 1961, the church voted to become a member of the United Church of Christ, a union in 1957 of the Evangelical and Reformed churches of the Midwest and Congregational-Christian churches of New England and other parts of the country.
The church is a member of the Middlesex Association and Connecticut Conference of the United Church of Christ. Ours is a congregational form of church policy, meaning that the covenant members are responsible with the Holy Spirit for the church’s faith, life, ministry, and mission.