Can I pray sunnah after Asr?

Ḥanafī: no. From the moment Asr is prayed (the app anchors conservatively to Asr's entry) no voluntary prayer is begun until Maghrib; doing so is makrūh taḥrīmī, to be avoided. Shāfiʿī: it depends on the cause. A sunnah tied to a present cause, such as greeting the mosque or the two rakʿahs after wuḍūʾ, remains valid after Asr; a pure voluntary prayer with no cause does not. Missed obligatory prayers are made up in this window in both schools, subject to the sunset caveat. Select what you intend below and read your own verdict.

Rulings differ by madhhab and by what you intend to pray - the live answer below is conditioned on both. Draft pending scholar verification; see the methodology.