Is the word só the same in Brazilian and European Portuguese?

Yes

The word "só" is semantically, grammatically, and orthographically identical in both Brazilian and Continental Portuguese. It functions as an adjective (meaning alone or solitary) and as an adverb (meaning only, just, or merely). The only significant difference is in pronunciation: in Brazil, the "ó" is typically pronounced as an open vowel [sɔ], whereas in Portugal, it tends to be a more closed vowel [so]. While the word itself is used identically, Portuguese speakers in Portugal often reach for synonyms like "apenas" or "sozinho" in certain contexts to express the same idea.

Brazilian Portuguese Examples

1. Eu estou só em casa hoje. (I am alone at home today.) *2. Só tenho dez reais na carteira. (I only have ten reais in my wallet.)
2. Ela ficou só depois que o namorado partiu. (She was left alone after her boyfriend left.)
3. Só quero um copo de água, por favor. (I only want a glass of water, please.)
4. O projeto só será entregue amanhã. (The project will only be delivered tomorrow.)

Portuguese (Continental) Examples

1. Eu estou sozinho em casa hoje. (I am alone at home today.)
2. Apenas tenho dez euros na carteira. (I only have ten euros in my wallet.)
3. Ela ficou sozinha depois que o namorado partiu. (She was left alone after her boyfriend left.)
4. Apenas quero um copo de água, por favor. (I only want a glass of water, please.)
5. O projeto apenas será entregue amanhã. (The project will only be delivered tomorrow.)