Objectives Consent forms that are difficult to understand may jeopardize informed consent. The aim of this study was to determine whether consent documents for cardiology-related procedures could be easily read and understood by patients with low health literacy. Methods All 37 cardiology-related consent forms with patient information material were retrieved from a publicly available suite of documents from one state in Australia. Two raters independently assessed documents and resolved discrepancies through discussion. Understandability was assessed using the Patient Education Materials Assessment Tool for Printed materials (PEMAT-P). Readability was assessed using the Gunning Fog Index, SMOG and Flesch Reading Ease formulas. Images were assessed using the 5C Image checklist. Results were analyzed descriptively. Results Only 1 of 37 forms met the general PEMAT-P threshold (70%) for being ‘understandable’. The average readability score was high, requiring a grade 10–12 level of education to understand. Most images lacked useful captions, had low visual clarity, and were not purpose-designed for the material. Conclusions The current format for cardiology consent forms does not meet recommended standards for understandability and readability. Practice implications Development of consent forms would benefit from taking health literacy principles into account with patient input, and purpose-designed images should be included in all forms to reinforce text.