Dietary education is a core component of cardiac rehabilitation (CR). It is unknown how or what dietary education is delivered across the United Kingdom (UK). We aimed to characterise practitioners who deliver dietary education in UK CR and determine the format and content of the education sessions. A 54-item survey was approved by the British Association for Cardiovascular Prevention and Rehabilitation (BACPR) committee and circulated between July and October 2021 via two emails to the BACPR mailing list and on social media. Practitioners providing dietary education within CR programmes were eligible to respond. Survey questions encompassed: practitioner job title and qualifications, resources, and the format, content and individual tailoring of diet education. Forty-nine different centres responded. Nurses (65.1%) and dietitians (55.3%) frequently provided dietary education. Practitioners had no nutrition-related qualifications in 46.9% of services. Most services used credible resources to support their education, and 24.5% used BACPR core competencies. CR programmes were mostly community-based (40.8%), lasting 8-weeks (range: 2-25) and included 2 (range: 1-7) diet sessions. Dietary history was assessed at the start (79.6%) and followed-up (83.7%) by most centres; barriers to completing assessment were insufficient time, staffing, or other priorities. Services mainly focused on the Mediterranean diet whilst topics such as malnutrition and protein intake were lower priority topics. Service improvement should focus on increasing qualifications of practitioners, standardisation of dietary assessment, and improvement in protein and malnutrition screening and assessment.