Plotinus’ innermost circle includes Porphyry, Amelius Gentilianus of Tuscany, the Senator Castricius Firmus, and Eustochius of Alexandria, a doctor who has devoted himself to learning from Plotinus and will attend to him until his death.

Other students include Zethos, an Arab by ancestry who dies before Plotinus, leaving him a legacy and some land in Campania; Zoticus, a critic and poet; Paulinus, a doctor of Scythopolis; and Serapion from Alexandria.

Plotinus has had students among the Roman Senate beside Castricius, such as Marcellus Orontius, Sabinillus, and Rogantianus.

Women are also numbered among his students, including Gemina, in whose house he has lived during his residence in Rome, and her daughter, also Gemina; and Amphiclea, the wife of Ariston the son of Iamblichus.

Finally, Plotinus is a correspondent of the philosopher Cassius Longinus.

At one point Plotinus had attempted to interest Gallienus in rebuilding an abandoned settlement in Campania, known as the 'City of Philosophers', where the inhabitants would live under the constitution set out in Plato's Laws.

An Imperial subsidy is never granted, for reasons unknown to Porphyry, who reports the incident.