Result conjunctions link a cause to its consequence. Where causal conjunctions point backward (because X), result conjunctions point forward (so Y). In English you have so, therefore, that's why, and as a result. Spanish has an equally rich set, and because these describe real consequences rather than intentions, they all take the indicative.
Así que: so, therefore
Así que is the most common conversational word for so in the sense of a consequence. It's everyday, neutral, and works in both speech and writing.
Por eso: that's why, for that reason
Por eso literally means because of that or that's why. It points explicitly back at a stated reason to explain the consequence that follows.
Estoy cansado; por eso no salí anoche.
I'm tired; that's why I didn't go out last night.
Llovió todo el día, por eso no fuimos a la playa.
It rained all day, that's why we didn't go to the beach.
Por lo tanto: therefore
Por lo tanto means therefore and belongs mostly to writing and formal speech. It's what you'd use in an essay, a legal opinion, or a presentation, where you want the logical flow to feel deliberate.
Los datos son claros; por lo tanto, debemos actuar.
The data is clear; therefore, we must act.
No cumplió con los requisitos, por lo tanto fue rechazado.
He didn't meet the requirements, therefore he was rejected.
A very close synonym is por consiguiente, equally formal.
De modo que / de manera que: result meaning
You've seen these phrases in the Purpose page with the subjunctive, meaning so that (with the aim that). When they express a real result instead, they switch to the indicative.
No estudió, de modo que reprobó el examen.
He didn't study, so he failed the exam.
Llegó tarde, de manera que perdió el vuelo.
She arrived late, so she missed the flight.
Compare this with the purpose reading: Habla lento *de modo que todos te entiendan* (subjunctive, purpose: so that they understand). Versus: Habló lento, *de modo que todos lo entendieron* (indicative, result: and as a result, they understood him).
Entonces: then, so
Entonces is a loose, conversational word that can mean then (time), so (result), or work as a general filler. As a result connector, it is the most casual option of all.
No contestó, entonces le mandé un mensaje.
She didn't answer, so I sent her a message.
No había taxis, entonces caminé a casa.
There were no taxis, so I walked home.
In writing, entonces is usually replaced by así que or por eso, which sound tidier on the page.
Summary
| Conjunction | Meaning | Register | Mood |
|---|---|---|---|
| así que | so, therefore | neutral | indicative |
| por eso | that's why | neutral | indicative |
| por lo tanto | therefore | formal | indicative |
| por consiguiente | consequently | formal | indicative |
| de modo/manera que | so (result) | neutral | indicative |
| entonces | then, so | casual | indicative |
Common mistakes
❌ Llovió mucho, por eso que no salimos.
Wrong: por eso does not take que — it stands alone.
✅ Llovió mucho, por eso no salimos.
Correct: por eso without que.
✅ Así que estudiamos más.
Correct: indicative after así que for a real consequence.
❌ Entonces, por lo tanto, no vamos.
Wrong: stacking two result connectors is redundant.
✅ Por lo tanto, no vamos.
Correct: use one result connector at a time.
For the cause side of the equation, see Causal: Porque, Como, Ya que. For broader sentence-to-sentence connectors, see Discourse Connectors.
Related Topics
- Causal: Porque, Como, Ya queA2 — How to express cause and reason in Spanish with porque, como, ya que, puesto que, and pues.
- Purpose: Para que, A fin de queB2 — How to express so that and in order that with para que, a fin de que, and related purpose conjunctions, all with the subjunctive.
- Discourse ConnectorsB2 — High-frequency discourse markers that link ideas across sentences and paragraphs in Spanish.