Aitutaki's best beaches are not on the main island but on the motus — the small coral islets that dot the rim of the lagoon. Most are uninhabited, accessible only by boat, and backed by nothing but coconut palms. The sand is fine and white, the water so clear you can watch fish from the surface without a mask. One Foot Island (Tapuaetai) gets the most visitors, but several other motus offer equally good swimming and snorkelling in quieter surroundings.
On the main island, Ootu Beach on the eastern peninsula is the standout: a long, open stretch of white sand with the lagoon immediately offshore, calm enough for wading and shallow enough for snorkelling without going far from shore. It sees far fewer visitors than the motu beaches and has a pleasantly unhurried feel. If you're staying on the main island, this is your easiest daily swim.