The construction, incorporation and behaviour of a simple and cheap coated tubular solid-state iodide-selective electrode into the conduits of a flow-injection system is described. The compact tubular membrane FIA system is stable and once the electrode is established, it requires minimum maintenance. Iodide can be determined in the range 5–2,000 mg/l with a sample frequency of about 90 samples per hour and a coefficient of variation of better than 1.8%.