What a UK CAS letter is, what it contains, how to get one, deposits and pre-CAS interviews for Bangladeshi applicants, validity rules and how to fix CAS errors.
A CAS letter is the document UK universities send to confirm your Confirmation of Acceptance for Studies (CAS), the unique reference number you need to apply for a UK Student visa. Officially, a CAS is not a paper letter but an electronic record that a licensed university creates in the Home Office's sponsorship system. Most universities email you a "CAS statement" showing the reference number and the details recorded about you and your course.
For Bangladeshi students, the CAS stage is often the hardest step between an offer and a visa: universities may ask for a large tuition deposit, financial documents and a credibility interview before they issue it. This guide explains what a CAS contains, how to get one, how long it is valid, and the mistakes to avoid.
Rules and university policies in this guide were checked on GOV.UK and official university websites in October 2026. Deposit amounts and pre-CAS procedures differ by university and can change, so always follow the instructions in your own offer and CAS emails.
Key Takeaways
A CAS is an electronic reference number issued by a licensed UK student sponsor. You must enter it in your Student visa application.
You need an unconditional offer before a university will issue a CAS, and most universities also require a tuition deposit and pre-CAS checks.
You must apply for your visa within six months of your CAS being issued, and no earlier than six months before your course starts.
A CAS can only be used once. If your visa is refused, you will normally need a new CAS for a new application.
Several universities apply higher deposits or mandatory pre-CAS interviews to applicants from Bangladesh, so check your university's policy early.
Check every detail on your CAS statement before applying; errors must be fixed by the university before you submit your visa application.
What Is a CAS Letter?
CAS stands for Confirmation of Acceptance for Studies. According to GOV.UK, it is a reference number that proves you have been offered a place on a course by a licensed student sponsor. The Home Office's student sponsor guidance describes the CAS as a virtual document held on its database, not a physical certificate.
Because universities usually send the CAS details as a PDF or email, many students and agents call it a "CAS letter". The terms CAS, CAS number, CAS statement and CAS letter generally refer to the same thing.
CAS vs offer letter
Offer letter: the university's decision on your application. It can be conditional or unconditional.
CAS: issued only after you hold an unconditional offer, have accepted it and have usually met the university's financial and document checks. It is the document the Home Office uses to link your visa application to your sponsor.
If you are still waiting to meet your offer conditions, read our guide on conditional vs unconditional offer letters.
What Information Does a CAS Contain?
The Immigration Rules (Appendix Student) and the Home Office's CAS creation guidance require the university to record details such as:
Your personal details: full name, date of birth, nationality, place of birth and passport number.
Course details: course title, academic level, start and end dates, latest date you can join, full-time study hours and the main study address.
Fees: first-year tuition fees, the amount already paid, any scholarship, and any university accommodation fees and payments.
English language: how your English was assessed, including test scores if a test was used.
Evidence used to obtain the offer: the academic documents the university relied on, such as SSC, HSC or bachelor's certificates and transcripts.
ATAS: whether your course needs an Academic Technology Approval Scheme certificate.
Sponsor note: extra information or minor corrections added by the university.
These details matter. The money you must show for your visa is based on the unpaid fees recorded on your CAS, and the documents listed under "evidence used to obtain offer" are the documents you should submit with your visa application.
How to Get a CAS from a UK University
Receive an unconditional offer. Meet any academic or English conditions in your offer.
Accept the offer. Follow the university's acceptance process and deadlines.
Pay the tuition deposit. Most universities require a deposit before they issue a CAS. The amount is stated in your offer or the university's CAS page.
Complete pre-CAS checks. Upload your passport, academic documents, English evidence and, if requested, financial documents. Some universities use online systems such as Enroly's "CAS Shield" for questionnaires and interviews.
Attend a credibility interview if required. The university may ask about your course choice, finances, study gap and career plans.
Receive your CAS statement. Check every detail as soon as it arrives.
Apply for your Student visa. Enter the CAS number in your GOV.UK application.
Teesside University, for example, says a CAS is normally issued within five working days once all its checks are complete, but it can take longer at peak times. Allow extra time before the September and January intakes. For the full visa process, see our complete guide to studying in the UK from Bangladesh.
CAS Deposits and Pre-CAS Checks for Bangladeshi Students
Universities must only issue a CAS when they reasonably believe the student will meet the Student visa requirements, and from June 2026 they face stricter Home Office compliance targets, including keeping their visa refusal rate below 5% (Student sponsor guidance). Many universities therefore run detailed checks before issuing a CAS, and some apply different rules by country.
Examples from official university pages (checked October 2026):
Coventry University lists the full first-year tuition fee as the deposit required to release a CAS for applicants from Bangladesh (Coventry application guide).
University of Bradford lists a standard deposit of £5,000 and £10,000 for students from Pakistan and Bangladesh (Bradford CAS page).
Birmingham City University lists Bangladesh among countries whose applicants complete an automated pre-CAS credibility interview and pay the full tuition fee before a CAS is issued (BCU CAS page).
Other universities may set different amounts, so read your offer carefully. Before paying any deposit, check the refund policy. For example, the University of Hertfordshire's 2027/28 fees policy refunds a deposit in full if no CAS has been issued, keeps £250 if a CAS has been issued, and may keep the full deposit where false documents or deception are involved.
To prepare for credibility questions, practise with our student visa interview questions guide for Bangladeshi students.
How Long Is a CAS Valid?
You must apply for your Student visa within six months of the date your CAS was issued. After that, it expires.
From outside the UK, you can apply no earlier than six months before your course start date.
A CAS can be used for only one visa application. If that application is granted or refused, the CAS cannot be reused. It may still be usable if an application was withdrawn or rejected as invalid.
If you change course, change university or need a new start date, you will normally need a new CAS.
Source: GOV.UK Student visa application guidance and Appendix Student.
How the CAS Is Used in Your Visa Application
CAS number: you enter it in the online application, and the Home Office checks it against its database.
Financial requirement: you must show the unpaid first-year tuition stated on your CAS, plus living costs of £1,171 per month outside London or £1,529 per month in London for up to nine months (GOV.UK money rules). Fees already paid and recorded on the CAS reduce the amount you need to show.
Documents: Bangladesh is not on the reduced-documentation list in Appendix Student, so you should submit your financial evidence and the academic documents listed on your CAS.
English: your CAS states how the university assessed your English, which must match what you submit.
Read our guide to bank statements and financial proof for a student visa from Bangladesh to prepare your funds correctly, and the cost of studying in the UK from Bangladesh for budgeting.
What to Do If Your CAS Has an Error
Check your CAS statement against your passport, offer letter and payment receipts. Pay special attention to your name, date of birth, passport number, course dates, tuition fees, fees paid and English test details.
Minor errors: the university can add a sponsor note to a CAS that has not yet been used.
Major errors: if key details are wrong, the university may need to cancel the CAS and issue a new one.
Timing: contact the university before you submit your visa application. Once a CAS has been used, it can no longer be updated with a sponsor note.
Differences between your CAS and your visa application can lead to delays or refusal, so never submit an application with incorrect CAS details.
Common CAS Mistakes to Avoid
Paying a deposit without reading the university's refund policy.
Missing deposit or document deadlines for your intake.
Giving answers in a credibility interview that do not match your SOP, documents or finances.
Not disclosing previous visa refusals when the university or visa form asks.
Applying for a visa before checking that your CAS details are correct.
Letting your CAS expire before you apply.
Using fake or altered documents. This can lead to refusal and long-term consequences for future UK applications.
Frequently Asked Questions
Is a CAS letter the same as an offer letter?
No. An offer letter confirms the university's admission decision. A CAS is issued later, after you hold and accept an unconditional offer and complete the university's checks.
How long does it take to get a CAS?
It depends on the university and the time of year. Some universities say a CAS is normally issued within about five working days after all checks are complete, but deposits, document checks and interviews can add time.
How long is a CAS valid?
You must use your CAS in a visa application within six months of it being issued.
Do I pay for a CAS?
The Home Office charges universities £55 for each CAS. Students do not usually pay a separate CAS fee, but most universities require a tuition deposit before issuing a CAS.
Can I use the same CAS after a visa refusal?
No. A CAS used in a refused application cannot be reused. You will normally need a new CAS from your university to reapply.
Do I need to upload the CAS statement with my visa application?
You must enter your CAS number. Keep the CAS statement ready, because you will use its details to complete the application and prepare your documents.
What happens in a pre-CAS interview?
The university checks that you are a genuine student. Expect questions about your course, university choice, academic background, study gaps, finances and career plans.
Get Help with Your CAS and UK Application
The CAS stage requires accurate documents, careful financial planning and confident interview preparation. Southern Trip Limited can help Bangladeshi students choose suitable UK universities, prepare documents for pre-CAS checks, review CAS details and plan their Student visa application. Admission, CAS and visa decisions are made by the university and UK Visas and Immigration, so our focus is on helping you prepare a complete and honest application.
Explore our student visa guidance service or contact Southern Trip Limited to book a UK counselling session.