A CAS Letter (Confirmation of Acceptance for Studies) is a unique 14-digit reference number issued by a UK university to international students after they accept their offer and meet all admission requirements. The CAS confirms that the university will sponsor the student’s studies in the UK and is required to apply for a UK Student Visa through UK Visas and Immigration (UKVI).
Although it is commonly called a CAS letter, it is actually an electronic record generated by the university and sent to students via email along with their CAS number and course details.
A CAS is usually valid for 6 months and can only be used once for a visa application.
After receiving their CAS, most international students begin preparing for visa applications, travel plans, and accommodation arrangements before arriving in the UK.
What is a CAS Letter UK?
A CAS Letter (Confirmation of Acceptance for Studies) is an electronic confirmation issued by a UK university to international students who have accepted an offer to study at that institution.
The CAS contains a unique reference number that the student must include when applying for a UK Student Visa.
Without a CAS number, students cannot submit a UK student visa application.
Key Points About a CAS Letter
• Issued by UK universities licensed by the UK government
• Contains a unique 14-digit CAS reference number
• Required for applying for a UK Student Visa
• Confirms the student’s admission to a specific course
• Includes academic and financial information related to the program
Universities usually send the CAS after verifying student documents and confirming the tuition fee deposit.
Why is a CAS Letter Important?
Required for UK Student Visa
A CAS number is mandatory for applying for a UK Student Visa. Without it, students cannot complete the visa application process.
Confirms University Admission
The CAS confirms that the student has been officially accepted by a UK university licensed by the government.
Used for Immigration Verification
UK immigration authorities use the CAS to verify a student's course details, qualifications, and financial information.
Helps Students Prepare for Relocation
Once students receive their CAS, they can begin planning:
• Visa application
• Travel arrangements
• Student accommodation
• Arrival in the UK
CAS Letter Processing Time
Most UK universities issue a CAS letter within 1-3 weeks after students complete the required steps.
Processing time may vary depending on:
• Document verification
• Tuition fee payment confirmation
• University processing timelines
Students should ensure all documents are accurate and submitted on time to avoid delays.
Requirements for a CAS Letter
To receive a CAS letter, international students must meet several requirements.
Academic Documents
Students must submit academic qualifications such as:
• High school certificates
• Bachelor's degree certificates
• Academic transcripts
English Language Test
Most universities require proof of English proficiency through tests such as:
• IELTS
• TOEFL
• PTE Academic
Tuition Fee Deposit
Universities often require students to pay a tuition deposit between £3,000 and £8,000 before issuing a CAS.
Required Documents
Common documents include:
• Valid passport
• Academic certificates
• English language test results
• University offer letter
CAS Number vs CAS Letter: What's the Difference?
These two terms are often used interchangeably, but they refer to different things:
- CAS Letter — the full document your university sends you. It contains your personal details, course information, tuition fees paid, and your unique reference number.
- CAS Number — the 14-digit reference code inside the CAS letter (e.g. X4T94937484748W). This is the specific string you enter into your Student visa application on the UKVI portal.
When immigration advisors or universities ask for your "CAS", they almost always mean the number. When UKVI asks for your CAS in the visa application, enter the 14-digit number exactly as shown on your letter.
Universities That Issue CAS Letters
Many UK universities are licensed sponsors under the UK immigration system and can issue CAS letters to international students.
Some popular universities include:
- Coventry University
- Northumbria University
- Ulster University
- Brunel University London
- University of Portsmouth
- University of East London
- University of Glasgow
- Anglia Ruskin University
- University of Bedfordshire
- University of Chester
- London Metropolitan University
- University of Greenwich
- University of Wolverhampton
- Sheffield Hallam University
- Middlesex University
- University of Hull
- Oxford Brookes University
How to Get Your CAS Number: Step by Step
- Accept your unconditional offer — your university will not begin the CAS process until you have a firm unconditional place.
- Pay your tuition deposit — most UK universities require a deposit (typically £1,000–£4,000) before issuing a CAS.
- Complete your university's CAS request form — this usually involves submitting your passport details, current visa (if applicable), and proof of English language qualifications.
- Wait for processing — standard processing takes 5–10 working days. During peak periods (June–September) allow up to 15 working days.
- Receive your CAS statement by email — your university emails you a CAS statement containing your 14-digit CAS number and a summary of what has been reported to UKVI.
- Check every detail carefully — verify your full name, date of birth, passport number, course title, and course start date match your passport exactly. Errors are a leading cause of visa refusals.
- Enter the CAS number into your visa application — log into the UKVI online application and enter your CAS number in the designated field.
How early can universities issue a CAS?
Most universities begin issuing CAS numbers no earlier than 3 months before your course start date. You can apply for your Student visa up to 6 months before your course starts (if applying from outside the UK) or 3 months before (if applying from inside the UK).What to Do After Receiving Your CAS
Receiving a CAS is an important milestone for international students. After receiving it, students should prepare for the next steps.
CAS Preparation Checklist
• Verify CAS details carefully
• Prepare financial documents for visa application
• Apply for the UK student visa
• Book student accommodation
• Plan travel arrangements
Thousands of international students arrive in the UK during each intake, so it is recommended to secure accommodation early before availability becomes limited.
Finding Accommodation After Receiving a CAS
Once students receive their CAS letter, finding accommodation becomes one of the most important steps before arriving in the UK.
University halls often have limited availability, which is why many international students choose private student accommodation near their campus.
Platforms like Acolyte Living help students explore verified housing options near major UK universities before arriving in the country.
Booking accommodation early can help students secure:
• Better locations near universities
• Early booking options
• Verified student housing
• A smoother relocation experience
How Long Is a CAS Valid?
A CAS number is valid for 6 months from the date it is issued. This means you must submit your Student visa application before the 6-month expiry date — not simply start it.
- A CAS can only be used once for a single visa application.
- If your visa is refused, your original CAS may have expired by the time you reapply — you will need to request a new one from your university.
- If your visa application is rejected as invalid (missing documents, not assessed on merit), you do not need a new CAS — the original remains usable.
- Universities may withdraw a CAS if you fail to respond to contact requests or do not arrive by your course start date.
What Happens If Your CAS Expires or Is Rejected?
If your CAS expires
Contact your university's international student admissions or visa compliance team immediately. They will assess whether a new CAS can be issued. In most cases this is possible, but it resets the process — you will need to resubmit supporting documents and wait for a new CAS number before reapplying for your visa.
If your Student visa is refused
A refusal does not mean your CAS is automatically cancelled. Check the expiry date on your original CAS statement. If it is still within the 6-month validity window, you may be able to reuse it for a fresh application. If it has expired, request a new CAS from your university before reapplying.
Common reasons CAS-related visa refusals happen
- Name or date of birth on the CAS does not match the passport
- Incorrect passport number recorded on the CAS
- Course details on the CAS differ from the offer letter
- CAS submitted outside the 6-month validity window
- Insufficient financial evidence to match the figures shown on the CAS
If you spot any error on your CAS statement, contact your university's visa compliance team before submitting your application. They can correct the record with UKVI — you cannot edit the CAS yourself.
CAS for the UK Student Visa: Full Checklist
Before submitting your Student visa application, confirm each item below:
- ☑ You have received your CAS statement by email from your university
- ☑ Your 14-digit CAS number is noted and ready to enter
- ☑ Your full name on the CAS matches your passport exactly
- ☑ Your date of birth on the CAS matches your passport exactly
- ☑ Your passport number on the CAS is correct
- ☑ Your course title, start date, and end date are accurate
- ☑ Tuition fees paid are correctly reflected on the CAS
- ☑ Your CAS was issued within the last 6 months
- ☑ You are applying no earlier than 6 months before your course start date (outside UK) or 3 months (inside UK)
- ☑ You have your financial evidence ready (bank statements showing maintenance funds for 28 consecutive days)
- ☑ Your ATAS certificate is obtained if your course requires it
- ☑ You have your tuberculosis test results if required for your nationality
CAS Letter FAQs
How long is a CAS letter valid?
A CAS letter is usually valid for 6 months from the date of issue.
Can I apply for a UK visa without a CAS?
No. A CAS number is mandatory for applying for a UK Student Visa.
How long does it take to receive a CAS letter?
Most universities issue a CAS within 1-3 weeks after verifying documents and receiving the tuition deposit.
When should students book accommodation after receiving CAS?
Students should start booking accommodation as soon as they receive their CAS, since student housing fills quickly before each intake.
How can international students find accommodation in the UK?
Students can explore verified student accommodation platforms like Acolyte Living, which help students secure housing near universities before arriving in the UK.
Conclusion
The CAS Letter (Confirmation of Acceptance for Studies) is one of the most important documents for international students planning to study in the UK. It confirms admission to a licensed university and is required when applying for a UK Student Visa.
After receiving a CAS, students should begin preparing their visa application, financial documents, travel plans, and accommodation arrangements.
Planning ahead ensures a smooth transition to the UK and allows students to focus on starting their academic journey successfully.
