Ilhabela is reached by ferry from São Sebastião on the mainland. The crossing takes about 15 minutes and ferries depart every 30 minutes throughout the day, with reduced service overnight. Pedestrians cross free of charge; there is a fee for vehicles. In peak summer (December to March) and on holiday weekends, vehicle queues can stretch for several kilometres along the mainland road — come early, arrive midweek, or leave the car behind.
São Sebastião is about 210 kilometres from São Paulo city. The most common approach is to take the Tamoios Highway (SP-099) east from the Vale do Paraíba, which winds down the Serra do Mar escarpment and reaches the coast at Caraguatatuba before following the shore north to São Sebastião. The drive takes around two and a half hours in normal traffic, but Friday afternoons in summer are notoriously slow. Bus services run from São Paulo's Tietê terminal directly to São Sebastião, with the journey taking roughly three to four hours; from there, a short taxi or local bus ride reaches the ferry terminal. Once on the island, local buses connect the town with the main western beaches and villages, but a rental car or scooter is useful for exploring further afield.