From the Klong Prao immigration sub-office to the District Office (Amphoe) in Ban Dan Mai where marriages to Thai nationals are registered, here is where each office sits, its hours, and its official site — verified against independent sources, with anything we could not confirm flagged rather than guessed.
For the island's police station, Tourist Police box, ambulance and other emergency numbers, see the separate Koh Chang emergency services guide — kept as its own page since it's a different kind of lookup (who to call right now) from the civil-administration offices below.
Primary and official sources are cited above. Government rules, fees and procedures in Thailand change over time and vary by office; always confirm current requirements with the relevant authority before relying on them. BAANLYY never takes paid placement in editorial content.
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