What is a CAS Letter and Why is It Important for UK Student Visa Applicants?

If you’re planning to study in the United Kingdom, one of the most important documents you’ll need is a CAS letter. Without it, your student visa application cannot proceed.

At TSEC Consultancy Ltd, we help students every step of the way — and understanding the Confirmation of Acceptance for Studies (CAS) is essential.

In this post, we’ll explain:

• What a CAS letter is

• Why it’s so important

• When and how you get it

• What it contains

• Common mistakes to avoid

Let’s get into it.

What is a CAS Letter?

CAS stands for Confirmation of Acceptance for Studies. It is a unique reference number (along with supporting details) that a UK university issues to an international student who has accepted an offer and met specific conditions.

Think of the CAS as a digital endorsement from your university that confirms:
“We are officially offering this student a place, and we expect them to study with us.”

This letter is a mandatory requirement for your UK Student Visa (previously known as Tier 4 Visa).

What Information Does a CAS Letter Contain?

A CAS is not just a letter — it includes very specific information sent electronically to the UK Home Office. You’ll also receive a copy for your own use.

It usually includes:

• Full name and personal details (must match your passport)

• Course name, duration, and start date

• Tuition fees and how much you’ve paid already

• Unique CAS reference number (you’ll input this in your visa application)

• Sponsor license number of the university

• Address of the university

• Whether you’ve met English language requirements

• Accommodation and other relevant notes

Important: Any mistake in these details can delay or negatively impact your visa application.

When Do You Receive the CAS Letter?

You’ll only receive a CAS after:

1. Accepting an unconditional offer from a UK university

2. Paying the required deposit (usually £3,000–£5,000)

3. Submitting required documents (e.g. passport, academic certificates, proof of funds)

Once those steps are complete, the university usually issues the CAS 4–6 weeks before your course starts.

You can only apply for a student visa 6 months or less before your course start date.

Why Is CAS So Important?

Without a valid CAS, you cannot apply for your UK student visa.

Here’s why the UK Home Office cares about it:

• It confirms you have a genuine offer from a licensed sponsor

• It shows the course is legitimate and full-time

• It proves you meet financial and language requirements

• It links your visa to your specific course and institution

At TSEC, we help students avoid delays by reviewing CAS details before submission and guiding them through what’s required.

Common CAS Mistakes to Avoid

1. Submitting the wrong passport name or details that don’t match your ID

2. Missing payment deadlines or documentation

3. Not meeting university conditions (e.g., English proficiency)

4. Assuming CAS = Visa — it’s just a part of the application

5. Applying for a visa with an expired CAS (must be used within 6 months)

TSEC Consultancy ensures all documents and payments are in order to prevent these issues.

How TSEC Consultancy Ltd Can Help You

• Guide you in selecting CAS-compliant universities

• Review your offer and condition checklist

• Double-check your CAS letter before visa submission

• Assist with financial documentation and visa filing

• Provide full support from admission to visa approval

We simplify the study abroad process for students and ensure you’re not left in the dark.

Ready to Study in the UK?

Let TSEC Consultancy Ltd guide you from admission to visa success with expert advice and proven experience.