The ASNC PhD is a research degree, examined, usually after three years of research, by a dissertation of up to 80,000 words. The criteria for obtaining the degree are that the dissertation represent a 'substantial contribution to knowledge' and that it also represents a realistic amount of work for three years' study. The Department can offer doctoral supervision on topics in a variety of early medieval languages and literatures (Old English, Old Norse, Medieval Welsh, Medieval Irish, Insular Latin), in the history of a comparable range of geographical areas (Anglo-Saxon England, Scandinavia, Ireland, Wales, Brittany, and Scotland), as well as in palaeography.

Applicants for the PhD who have not previously taken an MPhil, MA, or similar research foundation course in a closely related discipline to the one in which they wish to pursue their research, are usually required to take the MPhil course before they are registered for the PhD. Those with relevant masters qualifications who are admitted into the PhD programme are registered for the degree towards the end of their first year if progress has been satisfactory.

As part of a PhD student's learning and development, regular Graduate Seminars are held throughout each term, where papers are given both by current students and by guest speakers. In addition the Easter Term Graduate Symposium is a more informal setting in which students present their research in a variety of formats (including posters and round-table discussions). ASNC graduate students also organise their own annual day-long conference (Cambridge Colloquium in Anglo-Saxon, Norse, and Celtic), as well as being involved in the running of two inter-University conferences.