Quail Island Adventures runs trips out to Quail Island from B-Jetty on the Lyttelton waterfront, and holds a 4.7 rating from 28 Google reviews.
Island day trips live or die on timing. Sailings are usually limited, so check the last boat back before you set off up the track, and leave a buffer for lingering at the jetty. A good island outing pairs the crossing itself — harbour views, seabirds, a bit of local history — with a walk once ashore, so wear shoes that can handle gravel and grass. Weather on the water changes faster than on land, and a calm morning can turn breezy by afternoon. Regulars book ahead in summer, travel light, and carry their own water and lunch, since there is rarely a shop or café once you step off the boat.
Lyttelton, just over the hill from Christchurch, makes this an easy half-day escape from the city.