What is the CAS letter?
The Confirmation of Acceptance for Studies, or CAS letter, is an official document issued by a UK university to an international student who has firmly accepted an unconditional offer to study. This document is not a physical letter in most cases but a digital reference number linked to detailed information stored in the UK Visas and Immigration (UKVI) system.
The CAS letter serves as proof that you have been offered a place on a course and that the institution is willing to sponsor your student visa application. It includes essential details such as your personal information, the course title and level, start and end dates, tuition fees, amounts already paid and your unique CAS number.
It is important to note that the CAS is a one-time-use document, valid for six months and usable only for a single visa application. It is typically issued no more than six months before the start of your course and you can apply for your visa up to six months in advance if applying from outside the UK.
For anyone navigating the student visa process, understanding the CAS letter’s relevance in the UK’s system is essential. It forms the backbone of your visa application, and any discrepancies in the information it contains can lead to setbacks or even rejections. That is why ensuring your details are accurate and up to date is not just recommended—it is non-negotiable.
Importance of CAS number
The CAS number is more than just a reference code—it is the digital gateway to your student visa for the UK. Every international student applying under the Student Route visa category must present a valid CAS number issued by a licensed sponsor (the university). Below are the key reasons why this number holds such importance:
- Foundation of your visa application The CAS number links your visa application directly to the UKVI system, where all supporting details about your admission and eligibility are stored. It serves as proof that your university has verified your credentials and is officially sponsoring your visa.
- Verifies institutional sponsorship Only universities licensed by the UK Home Office can issue a CAS. By attaching your visa application to a valid CAS, you confirm that your offer comes from a recognised, compliant institution—one that meets all legal obligations of sponsoring international students.
- Ensures consistency in your documents The CAS encapsulates critical information including course start and end dates, tuition fee breakdown, deposits paid and your academic qualifications. UKVI uses it to cross-check the data in your application and financial statements. Even minor inconsistencies can result in a visa refusal.
- Limits to one-time usage A CAS number is valid for only one visa application. If your application is rejected or withdrawn, a new CAS must be issued—often requiring fresh documentation and possible delays. This makes it essential to get it right the first time.
- Supports your credibility as a ‘genuine student’ UKVI assesses whether an applicant is a genuine student. The CAS, when paired with supporting documents, helps demonstrate your academic intentions, course progression and financial preparedness, all of which strengthen your credibility in the eyes of visa officers.
CAS Letter Sample
Understanding what a CAS letter looks like can make the entire student visa process feel far more manageable. While each university may follow its own template, the core elements included in a CAS letter are governed by UKVI guidelines and remain fairly consistent across institutions. Having a clear idea of how a CAS letter is structured can help you verify whether all required details have been correctly included.
The sample below has been curated to reflect the format used by most UK universities. It outlines the essential components such as your personal details, sponsor information, course specifics, financial summary and the unique CAS number. While this example has been anonymised for privacy, it serves as a reliable reference to help you cross-check your own letter when you receive it.
Do note that the CAS is not usually issued as a downloadable document but is sent as a digital notification via email. This email will often contain the CAS number along with the accompanying details that the university has submitted to UKVI on your behalf. As an applicant, it is your responsibility to review these details carefully before proceeding with your visa application.
Sample CAS Letter – Confirmation of Acceptance for Studies
University of Eastshire
International Admissions Office
123 Academic Avenue
London, UK
Email: admissions@eastshire.ac.uk
Sponsor Licence Number: X1Y2Z3A4B5C6
CAS Number: E1FG2H3456J7890K
Date of Issue: 15 June 2025
Student Name: Priya Sharma
Date of Birth: 10 March 2004
Nationality: Indian
Passport Number: M1234567
Course Title: MSc Data Science and Artificial Intelligence
Course Level: RQF Level 7 (Postgraduate Taught)
Mode of Study: Full-time
Course Start Date: 20 September 2025
Course End Date: 15 September 2026
Academic Year: 2025–2026
Language of Instruction: English
Course Fees: £17,500
Amount Paid to Date: £5,000 (Deposit)
Outstanding Balance: £12,500
Accommodation Fees Paid (if any): £0
Evidence used to assess application:
- Bachelor of Technology in Computer Engineering – First Class
- IELTS (Academic) Score: Overall 7.0 (No band less than 6.5)
- Statement of Purpose
- Two academic references
Requirements and validity for CAS
Securing a CAS letter is not an automatic outcome of receiving an offer from a UK university. It is issued only after certain specific criteria are met, all of which are carefully evaluated by the institution. Here are the core requirements for obtaining a CAS, along with key insights on its validity:
- Unconditional acceptance of your offer Universities issue a CAS only once you have formally accepted an unconditional offer. This means that all academic, English language and administrative conditions tied to your admission must be cleared first.
- Verified academic documents and qualifications Institutions are required to assess the academic history of the applicant in detail. Your transcripts, degree certificates and references must be verified for authenticity before a CAS can be generated.
- Proof of English language proficiency Whether through IELTS, TOEFL, PTE or internal university assessments, valid proof of English language ability is a mandatory requirement under UKVI regulations—unless you are exempt due to nationality or prior qualifications.
- Initial tuition fee deposit payment Most UK universities require a tuition fee deposit—typically ranging from £2,000 to £5,000—before issuing a CAS. This not only confirms your commitment but also helps the university assess your financial readiness.
- Financial documents for credibility checks Some institutions conduct financial credibility interviews or require proof of funds even before releasing a CAS. This is to ensure students meet visa requirements set by UKVI.
- CAS validity period and usage A CAS is valid for six months from the date of issue and must be used within that window. However, your visa application cannot be submitted more than six months before your course start date. A CAS can only be used once—if your visa is refused or withdrawn, a new CAS must be issued.
Tip: Always double-check the information on your CAS before submitting your visa application. If even a minor detail—such as your passport number, course dates or payment status—is incorrect, it could delay your visa or lead to a refusal. Do not hesitate to ask your university to amend any discrepancies before proceeding.
How to apply for the CAS letter
Applying for a CAS letter is not a stand-alone task—it is an integrated part of your university application and visa preparation. Each university may vary slightly in its timelines or internal procedures, but the general steps below outline how to navigate the process, along with what to expect at each stage:
- Secure an unconditional offer from your chosen university A CAS will only be issued once all conditions on your offer letter have been met. This includes meeting academic entry criteria, demonstrating English language proficiency and submitting any required documentation such as references, personal statements or degree transcripts.
- Accept the offer formally through the university portal After receiving your unconditional offer, you must confirm your intention to study by officially accepting the offer on the university’s admissions portal. Some institutions may also require you to sign an agreement or declaration form before moving forward.
- Pay the required tuition deposit Most UK universities require an initial deposit—typically between £2,000 and £5,000—before a CAS is issued. This deposit is non-refundable in most cases and is deducted from your total tuition fee. Universities use this payment to assess your financial commitment and reduce the risk of visa refusals.
- Complete the CAS request form (if applicable) Some universities require students to complete a CAS request or pre-CAS questionnaire. This may include details such as passport information, past visa history, funding sources and previous academic qualifications. These forms are often used to conduct internal credibility checks.
- Undergo a financial credibility interview (in select cases) For applicants from high-risk countries or for courses with stricter compliance measures, universities may schedule a short credibility interview. This is to assess whether you meet UKVI’s genuine student criteria, including your academic motivations and financial preparedness.
- Provide updated documents as requested Your university may ask for scanned copies of documents such as your passport, final academic transcripts, proof of English language scores or financial statements. Ensure these are clear, valid and match the details you have submitted earlier.
- Receive the CAS email with your reference number Once all steps are complete, the university will generate your CAS and share the CAS number via email. This number is electronically linked to the UKVI database and is essential for your student visa application. Review all details thoroughly—errors cannot be corrected once submitted to UKVI without issuing a new CAS.
- Cross-check the CAS letter thoroughly After receiving your CAS, carefully review each detail—passport number, course title, dates, fees paid, qualifications. Any errors must be reported immediately, as the information is automatically fed into the UKVI system and will directly affect your visa application.
CAS letter deadline
The timeline for receiving your CAS letter is tightly linked to your university’s internal processes and the UKVI’s visa application window. While there is no single nationwide deadline, each university sets its own CAS issuance cut-off, typically around four to six weeks before the course start date. This buffer allows time for students to apply for their visa, receive a decision and make travel arrangements.
It is important to understand that a CAS is not issued automatically. If you delay accepting your offer, miss deposit payment deadlines or fail to submit required documents on time, your CAS could be delayed—or withheld altogether. Some universities operate on a ‘first-ready, first-issued’ basis, meaning that late submissions might result in you missing the CAS window, even if you hold an offer.
UKVI permits students to apply for a visa up to six months before the course begins. However, universities often stop issuing CAS letters around mid to late August for courses commencing in September. Always refer to the official university guidance and keep a close eye on emails, as most institutions clearly communicate their CAS deadlines in advance.
What is a Combined CAS Number?
A Combined CAS number is issued when a university includes both your pre-sessional and main academic course under a single Confirmation of Acceptance for Studies. This format is especially relevant for students who are conditionally admitted to a degree programme but must first complete a pre-sessional course—usually in English language or academic skills—before progressing to the main programme.
Rather than issuing two separate CAS numbers (one for each course), the institution merges both into one streamlined CAS. This enables you to apply for a single visa that covers the full duration of your study pathway, reducing the administrative burden and eliminating the need for a visa extension between stages.
However, not all institutions offer a Combined CAS by default. The courses must be consecutive, taught by the same university, and meet UKVI’s continuity requirements. Additionally, if the gap between the pre-sessional and the main course exceeds 30 days, a Combined CAS cannot be issued.
This arrangement benefits students by simplifying their visa process and avoiding additional costs. It also demonstrates to UKVI that your academic progression is planned and supported by the institution from the outset.
General CAS Letter Issuing Procedure
Securing a CAS letter is one of the final yet most crucial stages in preparing for your UK student visa. While each university may have its own internal workflow, most follow a general structure aligned with UKVI compliance standards. Here is a step-by-step overview of the CAS issuing process:
- Fulfil all conditions of your offer The process begins once you convert your conditional offer into an unconditional one. This involves submitting your final academic transcripts, English proficiency scores and any other documents your university requires for admission.
- Accept the offer formally After fulfilling all conditions, you must officially accept the offer through your university’s admissions portal. Some institutions also require you to sign a declaration of acceptance or respond via email to trigger the CAS process.
- Pay the tuition fee deposit A non-refundable deposit—usually between £2,000 and £5,000—is required to confirm your place. The payment also serves as a financial readiness indicator and is often a prerequisite before any CAS request is considered.
- Complete the CAS request form or pre-CAS check Universities typically ask students to fill out a CAS data check form, which reconfirms key details such as passport number, academic history, visa refusal history and course selection. Some institutions integrate this within their online applicant portal.
- Submit financial documentation if required A few universities request bank statements or financial proof at this stage, especially if the student’s country has a high visa refusal rate. This additional step is designed to screen out applications that may face problems during visa processing.
- Attend a credibility interview (if applicable) Selected applicants may be invited for a short video interview. This is not an assessment of your academic performance but a check on your motivation, awareness of your course and understanding of the UK study environment.
- University reviews and approves CAS issuance The international admissions or compliance team conducts a final audit of your file. A CAS is generated if all details are accurate and compliant with UKVI standards.
- The CAS letter is emailed to you Once issued, the CAS is sent via email, not as a physical document. It includes your unique CAS number and supporting information needed for your visa application.
