conjugation.subjunctive.present-irregular
Six truly irregular subjunctives: sea, esté, vaya, haya, sepa, dé
Only six verbs escape the yo-form recipe: ser → sea, estar → esté, ir → vaya, haber → haya, saber → sepa, dar → dé.
conjugationB1standardinternally_reviewedv1.0.0
Explanation
Because their yo forms don't end in -o (soy, estoy, voy, he, sé, doy), six verbs need their own subjunctive stems: sea, esté, vaya, haya, sepa, dé — then regular endings: seamos, vayan, sepáis.
Estar carries written accents on the stressed forms (esté, estés, estén) and dé takes one to distinguish it from the preposition de.
Everything else — including tener, venir, decir, conocer, the entire -go and -zco families — is covered by the yo-form recipe and is not, strictly speaking, irregular in the subjunctive.
Examples
I hope it's easy.
Region: global
I don't think they're going to come.
Region: global
When you're ready, let me know.
Region: global