This research paper delved into the critical issue of applying English as a Lingua Franca (ELF) assessment principles in local English language tests used for non-native English speakers in Iranian language institutes. A qualitative content analysis was made on 60 local tests, dissecting them into domains, dimensions, and rating rubrics to scrutinize their alignment with ELF assessment principles. The study unveiled that despite some alignment with ELF assessment principles, key aspects like local communicative context, intercultural competence, and linguistic diversity are often overlooked. In particular, writing and reading tests failed to fully reflect these principles, and listening and speaking assessments showed biases towards native English varieties. The study provides crucial insights for test developers to foster a more nuanced and accurate assessment of non-native English speakers' abilities. Moreover, it highlights the need to embed ELF principles into test construction, argues for broader assessment scopes and a focus on locally relevant tasks, and contributes to more equitable and contextually relevant English language proficiency tests by emphasizing linguistic diversity in assessment frameworks.