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Fluorescent receptors (<b>4a</b>–<b>4c</b>) based on (thio)ureido-functionalized hexahomotrioxacalix[3]arenes were synthesised and obtained in the partial cone conformation in solution. Naphthyl or pyrenyl fluorogenic units were introduced at the lower rim of the calixarene skeleton via a butyl spacer. The binding of biologically and environmentally relevant anions was studied with NMR, UV–vis absorption, and fluorescence titrations. Fluorescence of the pyrenyl receptor <b>4c</b> displays both monomer and excimer fluorescence. The thermodynamics of complexation was determined in acetonitrile and was entropy-driven. Computational studies were also performed to bring further insight into the binding process. The data showed that association constants increase with the anion basicity, and AcO⁻, BzO⁻ and F⁻ were the best bound anions for all receptors. Pyrenylurea <b>4c</b> is a slightly better receptor than naphthylurea <b>4a</b>, and both are more efficient than naphthyl thiourea <b>4b</b>. In addition, ureas <b>4a</b> and <b>4c</b> were also tested as ditopic receptors in the recognition of alkylammonium salts.