Background: This Consensus Workshop dealt with diagnostic methodologies in the context of surveillance, screening, assessment of stage and grade, prognosis, monitoring and prediction of periodontal status. Several elements provided the impetus for the workshop, including the limited quality of available research on diagnostic tests, the rapid development of new technologies, the implementation of the 2018 classification and the declarations of the World Health Organisation on diagnosis and oral health.

Aim: To update and evaluate the evidence on diagnostic methods, considering recent advances in knowledge and the implementation of the 2018 classification.

Methods: The European Workshop Committee of the European Federation of Periodontology guided the development of a consensus report after commissioning eight systematic reviews within three working groups. The reviews were discussed during the in‐person consensus meeting involving 70 participants from 21 different countries.

Results: Working Group 1 discussed innovations in traditional diagnostic approaches, justified manual probing as the reference standard and assessed the value of image‐based methods. Working Group 2 analysed diagnostic tests based on microbial and host biomarkers and genetic diagnostic tests. Working Group 3 covered emerging technologies to be used within dental and non‐dental clinical settings, focusing principally on the impact of questionnaire‐based assessments and artificial intelligence systems (AIS) in interpreting different data modalities.

Conclusion: Although manual periodontal probing is firmly established as the reference standard, additional approaches based on imaging, biomarkers, host genetics, questionnaires and the development of emerging applied data science methods (e.g., AIS) are increasingly integrated in periodontal diagnostics.