Confiável vs. fiável vs. de confiança vs. digno de confiança
These four Portuguese terms all translate to reliable or trustworthy, but they differ based on regional usage (Brazil vs. Portugal) and the level of formality. While confiável and fiável are often interchangeable adjectives regarding technical reliability, de confiança implies a proven personal track record, and digno de confiança is a more formal expression used to emphasize high moral character or validity.
Confiável
B1This is the most general and common adjective used in Brazilian Portuguese for both people and things. It indicates that someone or something is capable of being trusted. In European Portuguese, this word is also used but is slightly less common than fiável when referring to mechanical things.
Ela precisa de uma babá confiável para cuidar dos filhos.
(She needs a trustworthy babysitter to look after the children.)
Esta fonte de notícias não é muito confiável.
(This news source is not very reliable.)
O site parece seguro e confiável para compras online.
(The website seems safe and reliable for online shopping.)
Fiável
B2This adjective is the preferred term in European Portuguese (Portugal) for reliable, especially regarding mechanics, systems, or technology. In Brazilian Portuguese, fiável sounds more technical or academic and is rarely used in daily conversation, where confiável is preferred.
O motor deste carro é extremamente fiável e nunca avaria.
(This car's engine is extremely reliable and never breaks down.)
Precisamos de obter dados estatísticos mais fiáveis.
(We need to obtain more reliable statistical data.)
A conexão de internet nesta área não é muito fiável.
(The internet connection in this area is not very reliable.)
De confiança
B1This is a very common locution (phrase acting as an adjective) in all Portuguese-speaking regions. It implies a history of trust. You use de confiança for professionals you use regularly (like a mechanic or doctor) or close friends. It suggests proven trustworthiness.
Eu só levo o meu carro ao meu mecânico de confiança.
(I only take my car to my trusted mechanic.)
Ele é o meu braço direito e um homem de confiança na empresa.
(He is my right-hand man and a trusted man in the company.)
Pode deixar a chave com o porteiro, ele é de confiança.
(You can leave the key with the doorman, he is trustworthy.)
Digno de confiança
C1This phrases translates literally to worthy of trust. It is the most formal and emphatic option on this list. It is often used in literary, legal, or serious contexts to describe a person's character or the validity of a statement. It implies high moral standing.
O tribunal considerou a testemunha digna de confiança.
(The court considered the witness worthy of trust.)
Um líder deve ser honesto e digno de confiança.
(A leader must be honest and trustworthy.)
Esta pesquisa científica é séria e digna de confiança.
(This scientific research is serious and trustworthy.)
Summary
Use confiável as your go-to word in Brazil, and fiável as the standard generally in Portugal, especially for things. Use de confiança when talking about people or services you know well and have a history with. Save digno de confiança for formal writing or when you want to emphasize that someone strictly deserves to be trusted.