The authors agree that the surname derives from the place name Ascoli, identified with two Italian localities: Ascoli Piceno, capital of the province of the same name in the Marche, and Ascoli Satriano, a locality in the province of Foggia, in Puglia. F. Miranda adds that the Latin forms of the place name were Ausculum, Asculum and Asclum, the Oscan form Auhsclum and the Greek Ασκλον.

E. De Felice notes that the form Ascoli, linked to Ascoli Piceno, has its epicentre and greatest diffusion in the Marche, while the variants Ascolese, Ascolesi and, in part, D'Ascoli derive from Ascoli Satriano and extend from northern Puglia to the Naples area. E. Rossoni specifies that D'Ascoli is concentrated mainly in the Naples area and the Salerno area, with presence in Rome, Genoa, the Reggio Calabria area and the Palermo area, while the variant Dascoli appears in Barletta and in Calabria.

The authors also agree on the frequently Jewish character of the surname. De Felice and Miranda explain that Ascoli —and more rarely D'Ascoli— was adopted by Jewish families going back to an old community of Ascoli Piceno, which between the 17th and 18th centuries was forced to concentrate in the ghettos of Rome and Ancona. Rossoni adds that, although it is a typically Jewish surname, it is also borne by families without Jewish origin.