Is it necessary to translate consent (power of attorney) for traveling with a child to Thailand?

No, translation of notarized consent or power of attorney for taking a child abroad for vacation or other purposes to Thailand is not required. A power of attorney for departure is only needed in certain cases to present it to Russian border guards at the border, and they have no use for an English version of this document. In general, permission or power of attorney for a child to travel abroad in Russian, notarized, will only be required in cases where the child is traveling without at least one parent, or with one parent if the other parent has filed an application to prohibit the child's removal. If the child is traveling with at least a father or mother, then such permission does not need to be notarized.

For more details on the entry procedure to Thailand and visa regime, you can read here - https://nashaplaneta.net/asia/thai/viza-v-tailand

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Follow the link, all these questions are discussed in the chat - https://t.me/thailand_travel_chat