Era ora. If we unpack it, we can see we have the imperfetto (simple past tense) of the verb essere (to be). And then we have ora. It means "hour" or "time" if we put an article in front of it, but it is also an adverb, meaning "now." In the case of the expression, there is no article and so it's not exactly clear which part of speech is meant. It doesn't really matter, because it's an expression that never changes.
Note that in Italian, it's always in the past tense, the imperfetto to be precise. In English, on the other hand, we can say it in the past or the present, or we can leave the verb out altogether. To form this expression in English, we do add the word "about." "It's about time," or "It was about time," or just, "About time!" We might also say, "High time."
Era ora is a great expression and easy to use. There is always an imaginary exclamation point after it. When someone arrives late, it is something to say, but it's a veiled reprimand (meaning, "you're late!"), depending on one's tone and facial expression, so it should be used with care when directed at a person. It can also refer to a situation, such as a delayed train or delivery.
We have hunted through Yabla videos to find some examples you can watch and listen to.
Eccomi qua.
Here I am.
-Ce l'hai fatta. Era ora, Mirò!
-You did it. It was about time, Mirò!
Sono contenta che tu sia tornato giù.
I'm glad you came back down.
Captions 70-73, Gatto Mirò - EP6 Buon compleanno
Play Caption
Ragazzi, ho portato le birre.
Guys, I've brought the beers.
-Era ora!
-It was about time!
Meno male che qualcuno ha pensato di portare da bere,
Good thing that someone thought of bringing something to drink,
sembrava la festa delle medie! -Ecco qua.
it seemed like a junior high school party. -Here you go.
Captions 9-12, Il Commissario Manara - S1EP12 - Le verità nascoste
Play Caption
Manara is very late for his dinner at Toscani's house. That's why Toscani says, when he opens the door:
Era ora, eh!
About time, huh!
Che è?
What is it?
Ma che stai a fa' [che fai]?
But what are you doing?
-Con permesso? Permesso?
-Allow me to come in, may I?
Captions 28-31, Il Commissario Manara - S2EP1 - Matrimonio con delitto
Play Caption
Manara, being Manara, has grabbed the wine off the table, gone back to the door, and come in a second time (saying Permesso), pretending he has brought the bottle.
Here, the police went through all the bags of the bus passengers and it took a while.
Questo è l'ultimo e l'ispezione dei bagagli è finita.
This is the last one, and the inspection of the luggage is complete.
-I ragazzi hanno avuto le loro borse?
-Do the guys all have their bags?
-Tutti andati pure. Prego.
-They've all gone, too. Please.
-Era ora anche, eh.
-It was about time, too, huh.
Captions 47-50, Il Commissario Manara - S2EP9 - L'amica ritrovata
Play Caption
Eva goes to see her favorite counterfeiter after a long absence.
La ladra più bella del mondo!
The most beautiful thief in the world!
Era ora che te [ti] facevi rivede [rivedere].
It was high time you reappeared.
Sono passati tanti anni!
Many years have passed!
Captions 48-50, La Ladra - EP. 1 - Le cose cambiano
Play Caption
A friend chastising another for not going out enough.
Che c'è che non va?
What's wrong?
Niente, una storia con un uomo
Nothing, a relationship with a man
che rischia di diventare importante.
that's in danger of becoming important.
-Be', era ora, no?
-Well, it was about time, wasn't it?
Captions 45-47, La Ladra - EP. 8 - Il momento giusto
Play Caption
A relationship had been hampered by some psychological problems.
Fine dell'Edipo. -Era ora.
My Oedipus complex is over. -About time.
Caption 9, La Ladra - EP. 12 - Come ai vecchi tempi
Play Caption
Camilla's car has a hard time starting. When the motor finally turns over, era ora (it was about time)!
Forza, dai, dai, dai, ci siamo, ci siamo.
Come on, come on, come on, come on, we're there, we're there.
-Sì, ci siamo. -Ma quanno 'a cambi qua stufa [romanesco: ma quando lo cambi quel rudere]?
-Yes, we made it. -But when are you going to trade in that jalopy?
-Fatto, ecco.
-Done, there we go.
-Era ora. -Sei stato fortissimo.
-About time. -You were great.
Captions 27-30, Provaci ancora prof! - S2EP1 - La finestra sulla scuola
Play Caption
Era ora is a way of saying "finally!" And sometimes both expressions can be used together.
Be', hanno fatto la pace.
Well, they made up.
Era ora, finalmente.
It was about time, finally.
Captions 68-69, Provaci ancora prof! - S2EP2 Una mina vagante
Play Caption
Although Era ora works fine on its own, and that is the scope of this lesson, it can also be part of a sentence and will generally be followed by che, in which case we need the subjunctive.
Era ora che mi telefonassi (it was about time you called me).