Turkish tax statutes set the frame; the Ministry of Treasury and Finance then issues a tebliğ (communiqué) with the working detail — evidence standards, filing mechanics, definitional edges. For Law 7582 that text is Income Tax General Communiqué No. 333 (Official Gazette No. 33300, 4 July 2026): it created the İstisna Belgesi application with its year-end deadline, sourced services performed in Türkiye as Turkish income, and confirmed the lookback blockers through thirteen worked examples.
Implementing communiqué
·