Introduction Swimming skills are an evidence-based component of drowning prevention. However, in Australia, many children miss out on learn to swim education. Voucher programmes may reduce swimming lesson cost and increase participation, especially among priority populations. The First Lap voucher programme provides two New South Wales state government-funded $100 vouchers for parents/carers of preschool children to contribute to swimming lesson costs. This evaluation aims to determine the effectiveness of the programme in meeting objectives of increasing preschool-aged children participating in learn to swim programmes and building parent/carer knowledge and awareness of the importance of preschool-aged children learning to swim.

Methods and analysis A programme logic model was developed to explain the inputs, activities and intended outputs, and outcomes, which guided this mixed-methods evaluation design of quantitative and qualitative analysis within an impact/outcome evaluation. Baseline sociodemographic registration data will be provided by the parent/carer of each child participant and linked to swim school provider data on voucher redemption. Data will be collected on voucher use, knowledge, and attitudes to swimming lessons at registration and across two surveys. An economic evaluation will assess programme cost-effectiveness.

Conclusion This evaluation will determine impacts on participation rates in learn to swim programmes, particularly within priority populations. It will examine whether the programme has influenced attitudes and motivations of parents and carers toward learn to swim programmes and water safety, whether the programme has impacted or enhanced the ability of the aquatics sector to deliver learn to swim programmes and assess its cost-effectiveness.