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

No

While the spelling, grammar, and fundamental meaning of "noivos" are identical in both dialects, there is a difference in typical usage. In Brazilian Portuguese, "noivos" is the standard way to refer to a couple throughout their entire engagement period (effectively "the fiancés"). In Continental Portuguese, while the term can be used for the engagement period, it is much more naturally and specifically associated with the "bride and groom" on their actual wedding day or during the ceremony.

Brazilian Portuguese Examples

1. Os noivos estão planejando o casamento desde o ano passado. (The engaged couple has been planning the wedding since last year.)
2. Eles são noivos há bastante tempo. (They have been engaged for quite a long time.)
3. Os noivos decidiram fazer uma festa de noivado. (The engaged couple decided to have an engagement party.)
4. Já compramos o presente para os noivos. (We have already bought the gift for the engaged couple.)
5. Os noivos estão muito ansiosos para o grande dia. (The engaged couple is very anxious for the big day.)

Continental Portuguese Examples

1. Os noivos entraram na igreja ao som de uma marcha nupcial. (The bride and groom entered the church to the sound of a wedding march.)
2. O brinde foi feito em honra dos noivos. (The toast was made in honor of the bride and groom.)
3. Os noivos partiram para a lua de mel logo após a cerimónia. (The bride and groom left for their honeymoon right after the ceremony.)
4. A cerimónia dos noivos foi emocionante para todos os presentes. (The bride and groom's ceremony was moving for everyone present.)
5. Os convidados aguardam a saída dos noivos para o jantar. (The guests are waiting for the departure of the bride and groom for dinner.)