Purpose Academic library websites need evaluation to determine whether users can derive useful experiences while visiting them to perform tasks. This is more so because visiting an academic library website is by voluntary action rather than compulsion as is the case with university, polytechnic and college sites where students must conduct academic transactions that cannot be reasonably avoided. The result of such an evaluation provides signposts for improvement so that academic library websites can continue to be useful to their users. Therefore, the purpose of this paper is to assess the structural effectiveness of academic library websites in Nigeria. Design/methodology/approach The case study, research strategy and survey research approach were adopted for the study. Through a Web search, 14 universities, one polytechnic and one college of education were identified while three academic library websites were selected for the study. The evaluation of the websites was un-moderated and conducted remotely by user participants who were recruited across the three tertiary institutions under study. A five-point scale questionnaire served as the research instrument while data were presented in tables and analyzed using the median score. The Kruskall–Wallis test by ranks was used to test the null hypothesis at a five per cent level of significance. Findings Out of the 20 items presented for assessment, Group 1 and 2 disagreed to 11 (55 per cent) while agreeing on the remaining 9 (45 per cent) on Lib 1 and Lib 2 websites. Group 3 agreed to 11 (55 per cent) while disagreeing on 9 (45 per cent) on the Lib 3 website. The null hypothesis proposed for the study was rejected as the p-value of 0.04 was significant at p < 0.05. This indicated that most of the critical issues pertaining to design effectiveness were perceived to be ineffective. Originality/value The findings from this study call for a review of the design of academic library websites in Nigeria so that users can identify which websites are easier to use.