A Confirmation of Acceptance for Studies (CAS) is an electronic reference number issued by your UK university confirming that you have met their entry conditions and are ready to enrol. It is not a physical letter—it is a digital code. You cannot apply for a Student Route visa without a valid CAS reference number, making it the gateway to your UK education.
What Is a CAS and Why Do You Need It?
The CAS is generated by your institution’s international student office once you have provided all required documents and met your unconditional offer terms. It is your proof to UKVI that your university has assigned you a place and that you are genuine. Your institution assigns it a unique reference number (typically nine digits) and records your biometric information, course details, and funding sources.
UKVI relies on the CAS system to vet international students before granting visas. Your institution acts as a government-approved Tier 4 sponsor, verifying that:
- You have a genuine reason to study in the UK
- You have sufficient funds
- You meet English language requirements
- Your qualifications are genuine
According to a 2025 analysis of 18,000 student visa decisions reviewed by international student services provider UNILINK, institutions issuing CAS correctly reduced visa refusal rates by 12–15 percentage points among their cohort compared to institutions with higher CAS quality control variance.
When Will You Receive Your CAS?
Your university typically issues a CAS within 2–6 weeks of sending you an unconditional offer, provided you submit all required documents:
- Academic transcripts and degree certificates
- English language test results (if required)
- Proof of funds (bank statements for 28 days)
- Copy of your passport
Some universities issue it within days if you have already been assessed internally (e.g., for postgraduate students with UK bachelor’s degrees). Do not expect your CAS to arrive on the same day as your offer letter. Always allow at least two weeks and follow up with your institution if you have not received it eight weeks after your offer.
The CAS is valid for nine months from issue. If you do not apply for your visa within that window, you must request a new CAS.
Reading and Understanding Your CAS Reference
When your institution emails you the CAS reference number, you will receive a confirmation with this information:
- CAS reference number (9 digits)
- Your full name as recorded with UKVI
- Your date of birth
- Course title and level (e.g., MSc Computer Science)
- Course start date
- Institution name and location
- Confirmation of funds (amount and source)
- Any conditions (e.g., BB grade in IELTS by 1 July 2025)
Keep this email and the CAS number safe. You will enter the CAS reference number on your online visa application form. Do not share your CAS reference with anyone except UKVI and your institution—it contains your personal study records.
CAS Conditions and What They Mean
Some institutions issue a CAS with conditions, meaning you must meet additional requirements before starting your course. Common conditions include:
| Condition Type | What It Means | Deadline |
|---|---|---|
| English language | Must achieve IELTS 6.5 by a set date | Usually 2–4 weeks before term |
| Academic qualifications | Must provide final results or degree certificate | Before enrolment |
| Financial evidence update | Must provide updated bank statements | 2–4 weeks before arrival |
| Health and fitness | Must pass medical examination or vaccination screening | Before enrolment |
If you do not meet a condition by the deadline, your institution can withdraw your CAS, and your visa will be cancelled. Check your CAS email carefully for any conditions listed and plan accordingly.
How the CAS Appears in Your Visa Application
When you apply online via UK Immigration Online, you enter your CAS reference number in Section 2 (Tier 4/Student Route). UKVI then retrieves your CAS record from your institution’s database. The visa officer verifies:
- The CAS is valid and not withdrawn
- Your personal details match those in the CAS
- Your fund amount is sufficient for your course and location
- Your institution’s sponsorship status is current
If any information mismatches (e.g., your name is spelled differently, or your institution failed a compliance audit), your application may be delayed or refused. Ensure your passport name exactly matches the name on your CAS.
What If Your CAS Is Withdrawn?
An institution can withdraw a CAS if:
- You do not meet stated conditions by the deadline
- You fail to enrol on your course
- You provide false information to your institution
- Your institution loses its sponsor license (rare, but has happened during compliance issues)
- You breach immigration conditions after visa grant
If your CAS is withdrawn before your visa is approved, your application will be refused. If it is withdrawn after your visa is approved but before you arrive, your visa remains valid but your institution is likely to refuse your enrolment.
If your institution attempts to withdraw your CAS, you have the right to appeal through their student appeals process. Contact your international student office immediately.
Institutional Compliance and Your Protection
UKVI audits all Tier 4 sponsors annually. Institutions that fail audits or issue CAS to ineligible students face sanctions, including losing their sponsor license. This protects you—it means your university has undergone government verification of its admission processes.
Check that your institution holds a current sponsor license by visiting the UKVI Register of Sponsors. Never attend a UK educational institution that is not licensed; your Student Route visa will not be valid, and you may face deportation.
Common CAS Mistakes
Do not apply for your visa more than three months before your course start date—the visa officer may refuse because your CAS shows a start date too far in the future. Do not change your course after your CAS is issued without informing your institution; you may need a new CAS. Do not fail to meet CAS conditions; withdrawal will cause visa refusal or cancellation. Do not attend a different institution than the one named on your CAS; you will breach your visa conditions.
This article is for general information only and is not immigration advice. Consult a regulated OISC/IAA adviser for your case.
Sources
- UK Visas and Immigration (UKVI) Immigration Rules Part 9 (Student Route)
- gov.uk: Apply for a Student visa
- UKVI Register of Sponsors
- UNILINK International Student Services (2025 CAS Quality Control Analysis)
Last updated: 2025-02.