Greek has several ways to say “because” or “since,” and the choice tells the listener how the reason fits into the conversation. Γιατί commonly adds an explanation after a claim. Επειδή readily foregrounds the reason. Αφού and the variants with μια(ς) και/που present it as already known or easy to accept, while formal prose has more explicit alternatives.
γιατί: “why?” and “because”
Γιατί performs two closely related jobs. In a question it asks for a cause, “why?” In an answer or subordinate clause it introduces that cause, “because.” Context and punctuation make the function clear.
Γιατί έφυγες τόσο νωρίς;
yatí éfiyes tóso norís;
Why did you leave so early?
Έφυγα νωρίς γιατί ήμουν κουρασμένος.
éfiya norís yatí ímun kurazménos
I left early because I was tired.
Γιατί δεν απάντησες; — Γιατί δεν άκουσα το τηλέφωνο.
yatí dhen apándises; — yatí dhen ákusa to tiléfono
Why didn't you answer? — Because I didn't hear the phone.
In neutral narration, γιατί very often follows the main clause and supplies the explanation as new information. That is a strong information-structure preference, not a ban on initial position. It naturally begins an answer, as above, and it can open a new sentence that explains the preceding one.
Δεν θα βγω απόψε. Γιατί πρέπει να τελειώσω αυτή την αναφορά.
dhen tha vyo apópse. yatí prépi na telióso aftí tin anaforá
I won't go out tonight. Because I have to finish this report. (conversational explanation)
That final example is conversational and deliberately segmented. In more integrated formal prose, a single sentence with επειδή or another linker may flow better.
επειδή: foregrounding the reason
Neutral επειδή is the usual choice when the reason clause comes first and establishes the background for what follows.
Επειδή ήταν αργά, πήραμε ταξί.
epidhí ítan arghá, pírame taksí
Because it was late, we took a taxi.
Επειδή δεν είχαν πουληθεί αρκετά εισιτήρια, η συναυλία ακυρώθηκε.
epidhí dhen íchan pulithí arketá isitíria, i sinavlía akiróthike
Because not enough tickets had been sold, the concert was canceled.
The reason-first order makes the cause the frame through which the main event should be understood. Επειδή is also perfectly natural after the main clause:
Αργήσαμε επειδή είχε πολλή κίνηση.
aryísame epidhí íche polí kínisi
We were late because there was heavy traffic.
Conversely, initial γιατί is possible in an appropriate reply or marked explanatory context. The difference is therefore distributional and pragmatic, not an absolute rule that one word may only occur before or after its main clause.
αφού: “since / given that”
Causal αφού presents the reason as shared, obvious, or already available: “since,” “given that,” “seeing as.” It often supports a conclusion, suggestion, or reproach.
Αφού ξέρεις τον δρόμο, οδήγησε εσύ.
afú kséris ton dhrómo, odhíyise esí
Since you know the way, you drive.
Αφού δεν πεινάς, θα βάλω το φαγητό στο ψυγείο.
afú dhen pinás, tha válo to fayitó sto psiyío
Since you're not hungry, I'll put the food in the fridge.
The same word also means temporal “after”: Αφού έφαγε, έφυγε can mean “After he ate, he left.” Context and the logical relation distinguish temporal sequence from an accepted reason. The temporal use belongs to temporal conjunctions.
μια και, μιας και, μια που, μιας που: “seeing that”
Μια και, μιας και, μια που, and μιας που are all real causal frames meaning “seeing that / since.” They are conversational to neutral and often introduce a practical suggestion based on the present circumstances.
Μια και είσαι εδώ, βοήθησέ με με τα κουτιά.
mia ke íse edhó, voíthisé me me ta kutiá
Since you're here, help me with the boxes.
Μιας που το ανέφερες, πρέπει να συζητήσουμε το κόστος.
mias pu to anéferes, prépi na sizitísume to kóstos
Since you mentioned it, we need to discuss the cost.
There is no correctness contest among these forms. The versions with και and που, with or without final -ς on μια(ς), all occur in ordinary modern usage.
καθώς and formal causal phrases
Καθώς can mean causal “as/since” in careful writing, though it also has temporal meanings. It often presents a background reason without the conversational directness of γιατί.
Καθώς δεν υπήρχαν άλλα θέματα, η συνεδρίαση έληξε.
kathós dhen ipírchan ála thémata, i sinedhríasi élikse
As there were no other matters, the meeting ended. (formal)
Δεδομένου ότι means “given that” and is formal or academic. Λόγω του ότι means “due to the fact that” and is common in official or bureaucratic prose, although simpler επειδή is often stylistically lighter.
Δεδομένου ότι τα στοιχεία είναι ελλιπή, δεν μπορούμε να καταλήξουμε σε συμπέρασμα.
dhedhoménu óti ta stichía íne elipí, dhen borúme na katalíksume se simbérazma
Given that the evidence is incomplete, we cannot reach a conclusion. (academic)
Η εκδήλωση αναβλήθηκε λόγω του ότι ο χώρος δεν ήταν διαθέσιμος.
i ekdhílosi anavlíthike lógho tu óti o chóros dhen ítan dhiathésimos
The event was postponed due to the fact that the venue was unavailable. (formal/official)
These formal phrases make the causal relation explicit but can sound heavy in everyday conversation. The shorter noun construction λόγω + genitive, such as λόγω της βροχής, is another option when the cause is a noun rather than a clause.
Common Mistakes
1. Adding να after επειδή.
❌ Έφυγα επειδή να ήμουν κουρασμένος.
Incorrect—causal επειδή introduces an indicative fact, not a να-clause.
✅ Έφυγα επειδή ήμουν κουρασμένος.
éfiya epidhí ímun kurazménos
I left because I was tired.
2. Leaving the causal frame incomplete after μιας. Both μιας και and μιας που are complete, grammatical choices.
❌ Μιας ήταν αργά, φύγαμε.
Incorrect—complete the causal frame with και or που.
✅ Μια και ήταν αργά, φύγαμε.
mia ke ítan arghá, fíghame
Since it was late, we left.
3. Replacing ότι with που inside δεδομένου ότι.
❌ Δεδομένου που έβρεχε, ακυρώσαμε την εκδρομή.
Incorrect—the formal causal phrase is fixed as δεδομένου ότι.
✅ Δεδομένου ότι έβρεχε, ακυρώσαμε την εκδρομή.
dhedhoménu óti évreche, akirósame tin ekdhromí
Given that it was raining, we canceled the excursion.
Key Takeaways
- γιατί asks “why?” or supplies an everyday reason, most often after the main clause.
- επειδή is neutral and especially natural when the reason is foregrounded before its result.
- Causal αφού, μια και, μιας και, μια που, and μιας που present the cause as given or readily accepted.
- καθώς is careful/written; δεδομένου ότι and λόγω του ότι are formal.
- The position patterns of γιατί and επειδή are preferences, never absolute bans.
Related Topics
- Causal ClausesA2 — Arrange Greek reason clauses before or after a main clause, replace clauses with nominal causes, and connect a cause to its result.
- Subordinating Conjunctions OverviewA2 — Navigate Greek dependent clauses by function: complements, time, cause, purpose, result, concession, and condition, with the mood and aspect patterns each linker interacts with.
- Causal and Consecutive ConnectorsB1 — Connect Greek sentences by presenting a real-world consequence, logical inference, practical conclusion, or formally stated result.