Anticipating future events with "As soon as"
When you talk about an action that will happen immediately after another event in the future, Spanish requires the present subjunctive for the anticipated event. Because the event hasn't happened yet, it is treated as pending or uncertain.
To say "as soon as", you can use the phrase en cuanto. When talking about a future sequence, you will pair en cuanto + [present subjunctive] with a main clause describing a future action (such as ir a + infinitive, or a future tense).
Using "Apenas"
Another very common way to say "as soon as" is apenas. It works exactly the same way as en cuanto: when referring to a future sequence of events, follow apenas with the present subjunctive.
Notice that the "as soon as" clause can come at the beginning of the sentence or in the middle. When it comes first, it is usually followed by a comma.
Using "Tan pronto como"
Finally, you can use the phrase tan pronto como, which translates directly to "as soon as". Just like the other two phrases, it takes the present subjunctive when describing future actions.
En cuanto, apenas, and tan pronto como are completely interchangeable in these everyday scenarios, making them perfect for coordinating your daily routine.