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

Yes

The word "clientes" is identical in meaning, spelling, and grammar in both Brazilian and Continental Portuguese. The only difference lies in pronunciation.

In Brazilian Portuguese, the vowels are generally more open and clearly articulated. In Continental Portuguese, unstressed vowels often undergo "vowel reduction," meaning the "e" in "clientes" might sound much more closed, muffled, or even nearly silent (sounding more like a schwa) compared to the clearer Brazilian pronunciation.

Brazilian Portuguese Examples

1. "Nossos clientes são muito felizes com o serviço." (Our clients are very happy with the service.)
2. "Estou conversando com os clientes agora." (I am talking to the clients now.)
3. "O número de clientes cresceu muito este mês." (The number of clients grew a lot this month.)
4. "Preciso ligar para os clientes amanhã." (I need to call the clients tomorrow.)
5. "Temos clientes fiéis à nossa marca." (We have clients loyal to our brand.)

Continental Portuguese Examples

1. "Os nossos clientes estão muito felizes com o serviço." (Our clients are very happy with the service.)
2. "Estou a conversar com os clientes agora." (I am talking to the clients now.)
3. "O número de clientes aumentou imenso este mês." (The number of clients increased immensely this month.)
4. "Tenho de ligar para os clientes amanhã." (I have to call the clients tomorrow.)
5. "Temos clientes fiéis à nossa marca." (We have clients loyal to our brand.)