Levels of Pass With a Viva: What Each Outcome Is Called and Means
The levels of pass with a viva, from no corrections to major corrections, with the real outcome names, deadlines and referral rules at Cambridge, Oxford, Imperial and Bristol.
The levels of pass with a viva run from a pass with no corrections, through a pass with minor corrections, to a pass with major corrections. Below those sits referral, where the thesis is revised and examined again. What each level is called, how long you get and whether major corrections count as a pass all depend on your university.
This guide puts the real outcome names from four UK universities side by side: Cambridge, Oxford, Imperial College London and Bristol. It then shows how to read your own outcome letter, so you know which level you have and what it asks of you. Your own regulations always decide your case.
The levels of pass with a viva, in plain terms
A pass with corrections means the examiners accept the thesis once you make changes they ask for. A referral means the thesis is not yet at the standard and will be examined again after revision.
| Level | What it asks of you | Is the thesis examined again? |
|---|---|---|
| Pass with no corrections | Submit the final copy; at Imperial, typing errors can still be listed | No |
| Pass with minor corrections | Fix specific, limited points within a short deadline | No, the examiners check the changes |
| Pass with major corrections | Make larger changes within a longer deadline | No resubmission; the examiners check the changes, and at Oxford they may hold a second viva |
| Referral or resubmission | Revise substantially and resubmit | Yes, and a second viva may be held |
Two rules from the regulations make the table concrete. Cambridge says that after minor or major corrections, your examiners report that the corrected thesis is satisfactory before approval is confirmed (Cambridge, examination outcome). Imperial's top outcome, "Pass", still allows typographical amendments, due within one month (Imperial Regulations for Research Programmes 2026-27, para 108).
What four universities call each outcome
The same result can carry four different names. The table below uses each university's own wording and deadline, taken from the pages linked under it.
| Outcome | Cambridge | Oxford | Imperial | Bristol |
|---|---|---|---|---|
| No corrections | "Approval" | Not named as a separate outcome on the page we read | "Pass" (typing fixes within one month) | A: "Award unconditionally" |
| Minor corrections | "Minor corrections", 3 months | Minor corrections, two months | "Pass, subject to minor amendments", six months | B: "Award with minor errors", 28 days |
| Major corrections | "Major corrections", 6 months | Major corrections, six months | No pass outcome of this kind | C: errors or omissions "of substance", normally six months |
| Revise and examine again | "Revise and Resubmit", 12 months | Referral back, one year | "Not pass, major amendments required", 18 months | D: resubmit "in a revised form", normally 12 months |
| Fail at doctoral level | Lower degree or outright failure | No outright fail at first attempt | "Fail PhD" or "Outright Fail" | E to G: master's routes; H: "Fail" |
Sources: Cambridge, Oxford, Imperial, para 108, Bristol, regulation 22. Oxford's deadlines shown are for theses submitted on or after 12 October 2025. Earlier theses had one month for minor corrections and six terms for referral back.
Imperial also has an outcome the others do not list: "Not pass, further viva voce examination required". It applies when the thesis meets the criteria but the viva did not, and the candidate sits a further viva within six months. For what follows a fail, see our guide to what happens if you fail your viva.
Is a referral the same as major corrections in a UK PhD viva
No, not at any of the four universities here. Major corrections lead to the degree once the examiners accept your changes. A referral means a revised thesis goes back for a further examination.
The difference shows in the rules. Cambridge gives 6 months for major corrections but 12 months to revise and resubmit, and only after resubmission do the examiners decide whether a second viva is held. Oxford needs a new examiner appointment form (GSO.3) for a resubmission, and some referral options let the student choose between resubmitting for the DPhil or a lower award. Oxford's notes of guidance for examiners (GSO.20a) call a resubmission "a fresh examination".
Imperial is the naming trap. Its "Not pass, major amendments required" sounds like major corrections, but it works like a referral. The thesis does not meet the criteria, you resubmit within 18 months to the same examiners, and the outcome is available only at the first examination.
Bristol keeps the two apart by letter. Option C, errors or omissions of substance, must be corrected "to the satisfaction of all examiners" before the degree criteria are met. Option D says the student "has not met the criteria" and the work needs "significant revision and a resubmission", which Bristol allows once.
A viva with minor corrections: what it means and how long you get
A viva with minor corrections is a pass that depends on a short list of limited fixes. You make them, the examiners check them, and no new examination follows.
Bristol spells out what counts as minor. Its list covers typographical errors, small changes or additions to the text, references or diagrams, and corrections that do not need "a major reworking or reinterpretation of the intellectual content". It also warns that many small errors can add up to the more serious option C.
The deadline depends on where you are. Check yours on the day the result arrives:
- Bristol: 28 days from formal notification of the outcome
- Oxford: two months from receiving the list of corrections, which should come within two weeks of the viva
- Cambridge: 3 months from the email formally confirming the outcome
- Imperial: six months, with the amendments reviewed by the examiners or their nominees
Each deadline runs from a different event, so note the start date as well. For how to plan and present the changes themselves, see our guide to types of viva corrections and how to complete them.
How to read your outcome letter: a five-question decoder
Your letter may use a name that is not on any list you have seen. These five questions tell you which level you are on, whatever the wording.
- Does it say the degree will be awarded, or recommended for award, once changes are made? If yes, you have passed with corrections.
- Does it mention resubmission, further examination or new examiners? If yes, it is a referral, whatever it is called.
- Who checks your changes? One or both examiners checking a list points to corrections. A new examination points to referral.
- When does the clock start? Cambridge counts from the confirmation email, Oxford from receiving the list, and Bristol from formal notification.
- How many attempts do you have? Bristol allows one resubmission. Cambridge allows a maximum of three attempts at correcting the thesis where the submission deadline falls on or after 1 January 2026.
Write the answers at the top of your corrections file. If any answer is unclear, ask your graduate school office in writing before you start, so the reply is on record.
How often each level is given
We could not find a national UK figure. The best-known numbers come from a 2020 DiscoverPhDs analysis of Freedom of Information data from 14 UK universities, covering candidates who sat a viva between 2006 and 2017 (DiscoverPhDs, PhD failure rate).
Of the candidates in that data who passed, it reports approximately 5% with no amendments, 79% with minor amendments and 16% with major revisions. DiscoverPhDs notes that not every university gave a detailed outcome, so the exact breakdown may differ. Our guide to the PhD viva pass rate explains what this data can and cannot tell you.
These are past results, not a forecast for any one thesis. If you want to lower your own risk of a heavier outcome, our guide on how to avoid major corrections in your viva gives a pre-viva self-audit.
If your examination is a US dissertation defense
A US dissertation defense is decided by a committee, and each graduate school sets its own outcome names. Cornell, for example, says a student may conditionally pass an exam. We cover those outcomes in our guide to dissertation defense outcomes, using named US graduate school policies.
What Thesisroom does with this
The level you receive can turn on how well you can explain specific passages under questioning. Thesisroom's Defense Practice writes questions an examiner could ask, each tied to a specific passage or page of your own thesis. You can answer in writing or out loud, in three styles: Practice, Rapid round and Mock panel.
Defense Practice does not write answers or scripts. If you have a referral and a second viva is likely, you can use it on the revised thesis to rehearse explaining what you changed and why.
Frequently asked questions
What are the levels of pass in a PhD viva?
From highest to lowest: pass with no corrections, pass with minor corrections and pass with major corrections. Referral, where the thesis is examined again, comes next but is not a pass. Names differ: Bristol says "Award with minor errors", and Imperial says "Pass, subject to minor amendments".
Is major corrections still a pass?
At Cambridge and Oxford, yes: the degree follows once the examiners accept your changes, without a resubmission. Bristol's option C works the same way, though it says the criteria are met only once all examiners are satisfied. At Imperial, the outcome called "Not pass, major amendments required" is not a pass. It is a resubmission within 18 months.
Is a referral the same as major corrections?
No. Major corrections are checked by the examiners and lead to the degree. A referral means you resubmit and the thesis is examined again, sometimes with a second viva. Cambridge gives 6 months for major corrections and 12 months to revise and resubmit.
How long do you get for minor corrections after a viva?
It depends on the university. Bristol allows 28 days, Oxford two months for theses submitted on or after 12 October 2025, Cambridge 3 months and Imperial six months. Check when your clock starts, because each university counts from a different event.
Do you need a second viva after major corrections?
Not at Cambridge or Bristol, on the pages we read: the examiners check the corrected thesis and no second viva is mentioned. Oxford's examiner guidance says examiners may hold a second viva before reporting on major corrections. At Cambridge, examiners decide whether a second viva follows a resubmission.
Can you fail a viva outright?
At some universities. Cambridge, Imperial and Bristol list an outright fail or no-award outcome. Oxford says examiners cannot recommend an outright fail on the first attempt for DPhil, MLitt or MSc(Res) examinations.
Sources
- University of Cambridge: Examination outcome (PhD)
- University of Oxford: Research submission and examinations
- Imperial College London: Regulations for Research Programmes of Study 2026-27
- University of Bristol: Regulation 22, examination reports and guidance on corrections
- University of Oxford: Notes of Guidance for the Examination of Research Degrees (GSO.20a)
- Cornell University Graduate School: Taking exams
- DiscoverPhDs: PhD failure rate, a UK analysis (2020)
How this guide was made: Thesisroom drafted this guide with the help of AI writing tools, then checked every fact, figure and source by hand against the references linked above.