IntroductionMany women experience symptoms during pregnancy. Elevated and prolonged anxiety can have negative effects on the woman and baby. The RAPID intervention aims to provide suitable, timely support for women with mild-moderate anxiety. The RAPID intervention is based on social support, relational continuity, psychological and relaxation response theory, and comprises midwife facilitated group discussions, one-to-one support and directed self-help materials.Methods and analysisFour National Health Service Trusts in England that provide maternity care will be cluster randomised to the RAPID intervention plus usual care or usual care. At each intervention site, two midwives and two maternity support workers will facilitate the intervention over a 12-week period. Eligibility includes nulliparous women at 16–20 weeks of pregnancy (n=50) with self-report symptoms of mild-moderate anxiety. Community midwives will signpost women to the study. The aim of the study is to establish the feasibility of conducting a definitive trial to examine the effectiveness of the RAPID intervention in addition to usual care. The objectives are to assess recruitment and completion rates, and a qualitative assessment of women’s and facilitators’ experiences of participation. An estimation of change in the seven-item Generalised Anxiety Disorder scale will inform the sample size for a definitive cluster trial.Ethics and disseminationEthical approval was given by East Midlands—Derby Research Ethics Committee 14 March 2022 (REC Reference: 22/EM/0018). Findings will be made available through publication in peer-reviewed journals, conferences and to participants. A final report will be submitted to HEE/NIHR ICA awards committee for publication.Trial registration numberISRCTN12834758.