The church was long dated to the late 1100s, though a dendrochronological study of a timber in the south wall-plate has suggested a date as early as 1131, making the surviving nave one of the older parts of any church in the district. It was originally built with a straight-ended Romanesque chancel, of which only the nave survives today; the porch dates from 1920 and the sacristy from the 1960s.
Over the seventeenth and eighteenth centuries the interior was much altered. Decorative mural paintings were added, along with a Renaissance-style pulpit and a Baroque altarpiece. In the 1760s the medieval chancel was demolished and replaced by a new, wider one, roughly doubling the size of the building.
By the mid-nineteenth century the parish had agreed to share a new joint church with neighbouring Österplana, and in 1888 the bulk of Kestad's building—chancel, sacristy and porch—was demolished. Unusually, the medieval nave was kept and used for a time as a meeting hall rather than a church. The building was reconsecrated in 1925 after modest repairs, and in the 1960s a new chancel was reconstructed on the old medieval foundations, along with a further sacristy, in an effort to restore something of the church's original medieval proportions.
The walls and vaults carry decorative grotesque-style murals from the 1630s or 1640s, in the manner known as the Older Läckö School, since similar work was first commissioned for nearby Läckö Castle by Jacob De la Gardie. The paintings, featuring acanthus scrollwork, angel heads and mask-like faces, were later whitewashed but uncovered again in 1914; the mask motifs are said to be unusual survivals in a church setting, more commonly associated with castle interiors of the period.
Among the furnishings is a cylindrical Romanesque font from the early twelfth century, possibly older than the church itself, and part of a small group of similar fonts found almost exclusively in Västergötland. The oak pulpit bears the date 1691 and is carved in Renaissance style with arcaded panels imitating inlay work. Above the altar stands a reconstructed calvary group—a crucifix flanked by carved figures of Mary and John—the figures dated to around 1200 and among the older surviving woodwork in the church; the group was reassembled in the twentieth century and returned to its position on a beam in the chancel arch in 1991. The church also retains two undated medieval bells.