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Portugal Entry Requirements
The documents you must present at the Portuguese port of entry depend on your nationality. If you are an EEA national, you will only need an identification document to enter Portugal.

At the same time, if you are a non-EEA traveller wishing to visit Portugal, you will need to present the following when you show up at the Portuguese port of entry:

A valid passport or travel document. Valid for at least three more months beyond your planned exit date from Portugal/Schengen and issued within the last 10 years.
A visa – if you are subject to the Portuguese visa regime.

Aside from these documents, the Portuguese border officer may ask you a few questions about your trip to Portugal:

What is your purpose of visiting Portugal?
How long do you intend to stay in Portugal?
Where are you going to stay in Portugal? Etc.
You may be asked for documents to support your answers, such as an invitation letter by a Portuguese host, proof of lodging or a round-trip ticket. For more information in this regard, contact the local consular services of Portuguese in your home country.

Keep in mind that the border police holds the final decision if you shall be permitted to enter Portugal or not. If the Portuguese border officer concludes that you are no risk for Portugal, upon checking your documents, you will be permitted to enter Portugal, and thus the Schengen territory.

Please, make sure that the Portuguese border officer stamps your passport when you enter Portugal. Without a stamp, you could be fined or detained from Portugal.

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