What Is a CAS Letter? The UK Student Visa CAS Explained (2026)
Every UK Student visa application starts with the same 14 characters. The CAS — Confirmation of Acceptance for Studies — is the university-issued reference that unlocks the visa form, defines how much money you must show, and lists the exact documents UKVI expects from you. Despite the name "CAS letter", it is not a paper letter at all. Here is exactly what a CAS is, how to get one in 2026, and the CAS mistakes that delay or sink applications.
What is a CAS?
A CAS is an electronic record that a licensed UK student sponsor (your university) creates on UKVI's system when it agrees to sponsor your studies. What you receive by email is a CAS statement — a summary showing your unique 14-character CAS number and the information the university reported to UKVI. You enter that number in your visa application, and UKVI checks everything you submit against it.
Two things follow from this. You cannot apply for a Student visa without a CAS. And because the CAS is the version of events UKVI treats as authoritative, any mismatch between your CAS and your application — course dates, fees, even name spelling — causes delays or refusals.
What your CAS contains
- Your personal details, exactly as the university holds them (check them against your passport).
- Your course title, level and mode of study.
- Course start and end dates — these determine your visa length.
- Your first-year tuition fee and any fees already paid (deposit and accommodation payments the university confirms).
- The evidence used to make the offer — the qualifications UKVI may ask you to produce.
- How the university assessed your English language ability.
- The university's sponsor licence number.
CAS vs offer letter — what's the difference?
| Offer letter | CAS | |
|---|---|---|
| What it is | The university's academic admission decision | An immigration record for your visa application |
| When you get it | After your application is assessed | After you accept an unconditional offer and pay your deposit |
| What it's for | Confirms your place (conditional or unconditional) | Required to submit the Student visa application |
An offer letter — even unconditional — gets you nothing at the visa stage. Only the CAS does.
How to get your CAS, step by step
- 1. Meet every condition of your offer so it becomes unconditional — results, transcripts and English evidence. If you are worried about IELTS, see the universities that accept alternatives in our guide to studying in the UK without IELTS.
- 2. Accept the offer and pay the deposit. Most universities require a tuition deposit — commonly £2,000–£5,000 — before starting the CAS process. Every pound recorded on the CAS as paid is a pound less you must show in the bank.
- 3. Complete the CAS questionnaire — and pass the credibility interview if invited. Universities pre-screen applicants before issuing a CAS, because refusals count against their sponsor licence. Weak or rehearsed answers about your course choice and funding are the most common reason a university quietly declines to issue a CAS.
- 4. Check the draft CAS statement. Most universities send one before assigning the CAS. Verify your name, dates, fees and course details line by line — this is your one easy chance to fix errors.
- 5. Receive your CAS number by email, usually within a few days to two weeks of completing the steps above. Universities generally issue a CAS no earlier than about 6 months before the course starts.
How long is a CAS valid?
You must use your CAS in a visa application within 6 months of it being assigned. Three rules catch people out:
- A CAS is single-use. Once used in an application — approved or refused — it is spent. A refusal means a new CAS before you can reapply.
- Deferring your intake voids the plan. Moving from September to January means new course dates, so the university must issue a fresh CAS.
- Don't sit on it. The strongest position is applying as soon as the CAS arrives and your 28-day funds history is complete — visa timelines are covered in our guide to UK Student visa processing times.
CAS and your proof of funds
Your CAS sets the financial target for your application: first-year tuition minus fees already paid, plus the monthly maintenance amount for your location. That money must sit in an eligible account for 28 consecutive days before you apply. The full calculation, with a worked example for Pakistani applicants, is in our guide to the bank statement for a UK Student visa — and the complete document list is in the UK Student visa requirements checklist.
Frequently Asked Questions
Is a CAS a visa guarantee?
No. A CAS confirms the university's sponsorship, but UKVI makes its own decision on your funds, documents and credibility. Applications with a genuine CAS are still refused — usually over financial evidence.
How long does a CAS take after paying the deposit?
Typically a few days to two weeks, once your offer is unconditional and any CAS interview is passed. In the August rush it can take longer — chase your admissions contact if nothing arrives within two weeks.
What if my CAS has an error?
Tell the university before you apply. A sponsor can add a note or issue a corrected CAS. Applying with a known error — even a small fee discrepancy — invites a refusal.
Can I use one CAS for two applications?
No. Each CAS supports exactly one visa application. If your application is refused or your plans change, you need a new CAS from the university.
What is a CAS interview?
A short credibility interview many universities hold before issuing a CAS — questions about why this course, why this university, your funding and your plans after graduating. Treat it as seriously as the visa itself: no CAS, no application.
From offer to CAS to visa, the order and timing of each step decide whether you fly on time. Global Pathways manages the whole chain — offer conditions, deposit, CAS checks and the visa application itself. Book a free consultation.