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If you should decide to stay longer in Thailand than 30 days and haven't applied for a regular visa in advance, you can apply for a 7-days extension at a fee of 1,900 Baht at your local immigration office. (If you travel with a 60-day tourist visa, you may extend your stay for 30 days.)

Required documents include the fully-filled extension form (TM. 7), a copy of your passport and a passport picture (4x6cm). For updates and downloads of visa extension forms, please visit the Pattaya Immigration Bureau website.