UK CAS Number 2026: Guide, Validity, Errors & Use

UK CAS Number 2026: What It Is, Validity, Errors & How to Get It

UK CAS Number 2026: Learn what a CAS is, how to request it, validity rules, common errors, and when you need a new CAS for your UK student visa.

UK CAS number is the most important reference you receive from your institution before applying for a UK Student visa, yet it remains one of the least-explained terms in the entire process. Every international student who needs a UK Student visa must obtain a CAS before the application can be submitted. Most receive it by email, enter it on the form, and move on without understanding what it is, what it contains, or what to do if something on it is wrong. That gap causes delayed applications and preventable refusals.

This guide covers what the CAS number is and what it is not, what the record contains, how to request it, how to use it in the visa application, how to fix errors, when it expires, when you need a new one, and the academic progression and 5-year study rules that govern whether a CAS can be issued at all.

If you are still building your understanding of the broader visa process, the UK Student Visa 2026: Complete Application Guide covers every stage from offer acceptance to approval.

Table of Contents

1. UK CAS Number at a Glance: Key Facts for 2026
2. What Is a UK CAS Number and Why Do You Need One?
3. What Information Does Your UK CAS Number Contain?
4. How to Get Your UK CAS Number: Step-by-Step Process
5. UK CAS Number Timelines: When Will Your Institution Issue It?
6. How to Use Your CAS Number in the UK Student Visa Application
7. What to Do If Your CAS Contains Errors or Cannot Be Issued
8. CAS Expiry and When You Need a New CAS Number
9. Academic Progression and the 5-Year Study Limit for CAS Eligibility
10. Frequently Asked Questions About the UK CAS Number
11. Important Notice

UK CAS Number at a Glance: Key Facts for 2026

Key Facts Every CAS Applicant Should Know

The Detail Most First-Time Applicants Get Wrong

The CAS number is not a document to print or attach to the visa application. The full name is Confirmation of Acceptance for Studies. You enter the 14-character reference in the designated field on the UKVI online application form, and UKVI officers retrieve the full CAS record directly from their system using that number alone. Applicants who search for a PDF to upload are looking for something that does not exist.

What Is a UK CAS Number and Why Do You Need One?

The UK Student visa application cannot be submitted without a valid CAS. According to the GOV UK Student visa requirements page, a CAS is a mandatory requirement for every applicant on the Student Route. No other document replaces it, and no exemption exists for any category of international student.

The CAS as the Foundation of the UK Student Visa

The confirmation of acceptance for studies UK is the mechanism through which UK immigration law connects your visa application to your institution’s willingness to sponsor your studies. Without a valid CAS from a UKVI-licensed institution, the application cannot proceed. The CAS is not optional, cannot be substituted by an offer letter or acceptance email, and cannot be generated by anyone other than a licensed sponsor institution.

What the CAS Is and What It Is Not

What It Is

In terms of CAS number format characters, the reference is always 14 alphanumeric characters, generated by UKVI‘s Sponsor Management System at the institution’s request. This code unlocks the institution’s electronic sponsorship record in UKVI‘s database. When you enter it on the visa form, UKVI officers access every detail of your offer, including course, fees, and qualifications assessed, without any separate CAS document required.

What It Is Not

The CAS is not a physical letter, not a PDF, and not the same as the offer letter. You do not print, upload, or attach it to the visa application. Only the 14-character number is entered on the form. Many applicants waste time searching for a CAS document to attach when no such document exists.

Why Only Licensed Sponsors Can Issue CAS Numbers

Not every UK educational institution is eligible to issue a CAS. UK immigration law requires institutions to hold a valid UKVI sponsor licence for the Student Route. A student who accepts an offer from an institution that is not a UK licensed student sponsor CAS issuer cannot receive a CAS and cannot apply for a UK Student visa on that basis.

If you are still comparing destinations, the USA vs UK vs Canada vs Australia 2026: Study Abroad Guide sets out visa frameworks, costs, and post-study pathways across all four major destinations. Always verify sponsor licence status before accepting any offer.

What Information Does Your UK CAS Number Contain?

Knowing what does CAS number contain UK visa allows you to cross-check every field against your passport before applying.

Student Personal Information

Name and Passport Details

The CAS contains your full name exactly as it appears on your passport, including middle names and second family names. It also records your date of birth, nationality, country of birth, and current passport number. UKVI cross-checks every field against the passport, and any discrepancy may result in refusal.

Why Name Matching Matters

UK immigration rules require that all information submitted to UKVI exactly matches the passport. A middle name omitted, a hyphen missing, or a name component in the wrong order can trigger a refusal. Cross-check the CAS statement against your passport as soon as the number arrives, report any discrepancy to the institution immediately, and do not proceed with the visa application until the CAS record matches the passport exactly and the institution has confirmed it.

Course and Institution Details

Course Information

The CAS contains the full course name, RQF qualification level, course start date, and expected end date. UKVI uses these dates to determine the length of the Student visa. Incorrect course dates on the CAS may result in a visa granted for the wrong period of study.

Institution and Sponsor Details

The CAS includes the institution’s name and UKVI sponsor licence number, allowing UKVI to verify that the institution holds a current, valid licence at the point of application. Avoid unnecessary delays between receiving the CAS and submitting the visa application.

Financial Details on the CAS

The financial fields on the CAS connect directly to your visa maintenance evidence requirements. For a full breakdown of how the outstanding fee figure on your CAS affects the bank statement evidence you need, see the Student Visa Financial Proof: Bank Statement Requirements guide.

Tuition Fees and Payments

The CAS shows the total tuition fee for the programme and the amount already paid. UKVI uses the outstanding fee figure, alongside your own maintenance funds, to calculate the total financial evidence required.

What to Do If Fees Look Wrong

If the CAS shows zero paid despite a deposit being made, this is commonly because the payment had not yet been processed when the CAS was generated. This is not automatically a problem, as you submit your own financial evidence separately. If the total fee amount is incorrect, contact the institution to request a correction before applying.

How to Get Your UK CAS Number: Step-by-Step Process

Understanding how to get CAS number UK starts with the pre-conditions that must all be satisfied before the institution can initiate the request. The CAS number student visa 2026 application sequence cannot be skipped or reordered.

Step 1: Receive and Accept an Unconditional Offer

A CAS cannot be issued until you hold an unconditional offer and have formally accepted it. A conditional offer, where exam results, language scores, or other requirements remain outstanding, does not qualify. Do not contact the institution about a CAS before the offer is unconditional.

Step 2: Pay the Required Deposit

Deposit Requirements

Most UK institutions require a deposit before initiating the CAS process. Amounts vary by institution. Some students are exempt, including those on full institutional scholarships, government-sponsored students, and certain applicants under UKVI differentiation arrangements. Confirm the deposit requirement and any exemptions before making payment.

Deposit and CAS Timing

Allow 3 to 5 business days for the deposit to be confirmed in the institution’s finance system before following up with the CAS team.

Step 3: Submit Pre-CAS Documents to the Institution

Documents Typically Required

Before generating the CAS, the institution must verify that you meet the programme’s entry requirements. Documents typically requested include a passport biographic copy, academic qualifications and transcripts, English language test results, and an ATAS clearance certificate if applicable. Follow the institution’s checklist precisely.

ATAS Certificate

For certain postgraduate courses in sensitive subject areas, including aspects of biotechnology, nuclear physics, advanced materials, and artificial intelligence, UKVI requires an Academic Technology Approval Scheme (ATAS) certificate before the CAS can be generated. Apply for ATAS as early as possible since processing typically takes several weeks.

Step 4: Confirm the Draft CAS Details

The Draft CAS Review

Some institutions provide a draft CAS for review before locking the record in the UKVI system. Check every field against your passport: name spelling, date of birth, course dates, tuition fee amounts, and ATAS indication. Corrections are significantly simpler before the CAS is confirmed than after.

If No Draft Is Provided

Not all institutions offer a draft. If yours sends the final CAS number directly, check the statement email immediately and contact the institution if any error is found. The same correction process applies regardless of whether the CAS is in draft or final status.

Step 5: Receive the CAS Number by Email

The institution emails the CAS number to your registered address alongside the CAS statement summarising the record. Most institutions issue within 5 to 10 working days after all pre-conditions are met. If the CAS has not arrived within 10 working days, contact the institution’s international admissions or immigration team.

UK CAS Number Timelines: When Will Your Institution Issue It?

When to request CAS number UK depends on your application location and the UKVI-permitted issuance window for your course start date.

Issuance Windows by Application Location

Applying From Outside the UK

For students applying from outside the UK, the institution may issue the CAS up to 6 months before the course start date. You may then apply for the visa up to 6 months before the course begins. Most institutions open their CAS issuance schedule from March or April for September starts. Confirm the institution’s specific calendar rather than assuming it aligns with the maximum UKVI window.

Applying From Within the UK

For students already in the UK needing to extend or switch course, the institution may issue the CAS up to 3 months before the start date. If your current visa expiry creates urgency, contact the institution’s immigration team early and explain the deadline. No institution can issue the CAS outside the UKVI-permitted window regardless of circumstances.

Why Institutions Cannot Issue CAS Numbers Too Early

UKVI rules cap how far in advance a CAS can be issued. An institution cannot generate a CAS for a September course in January even if every pre-condition is satisfied. Build your application timeline around the institution’s earliest CAS issuance date.

Planning the Full Application Timeline

Outside UK Application Recommended Timeline

Accept the unconditional offer and pay the deposit as soon as all conditions are met, then submit pre-CAS documents immediately. The CAS window typically opens 4 to 6 months before the start date. Apply for the visa as soon as the CAS arrives within the 6-month validity window. Allow at least 3 weeks for standard UKVI processing.

Inside UK Application Recommended Timeline

Request the CAS at least 6 weeks before your current visa expiry, or as early as the 3-month window allows. Apply for the extension as soon as the CAS is received. Do not allow the current visa to expire before the new application is submitted.

How to Use Your CAS Number in the UK Student Visa Application

The UK Student visa application is completed online through the UKVI portal. The GOV UK apply for a UK Student visa page lists every document required alongside the application. The CAS number visa application form field is a dedicated entry box where you type the 14-character reference directly. No CAS document is uploaded or attached at any point.

Entering the CAS Number on the Application Form

Accuracy When Entering the CAS Number

Type the CAS number exactly as it appears in the institution’s email. A single incorrect character means UKVI cannot locate the record and the application stalls. If the system returns an error, contact the institution to confirm the exact reference before retrying.

One CAS Per Application

Each CAS can only support one visa application. Once submitted, the CAS is attached to that application and cannot be reused, even after a refusal or withdrawal. Understand the reuse rules before submitting, as they affect how you approach a reapplication.

What UKVI Does With the CAS Record

A UKVI officer retrieves the full CAS record using the number you entered and uses it to verify that the institution is a current licensed sponsor, the course is Student Route-eligible, your personal details match the passport, the financial information aligns with your submitted evidence, and the application falls within the valid CAS window.

What the CAS Does Not Replace

A valid CAS does not mean the application is complete. You must still provide a valid passport, financial evidence, English language results where applicable, an ATAS certificate if required, and any additional documents on the UKVI checklist. The CAS confirms institutional sponsorship only.

What to Do If Your CAS Contains Errors or Cannot Be Issued

The CAS errors what to do UK process always starts the same way: identify the error in the CAS statement, contact the institution’s immigration team immediately, and do not submit the visa application until the correction is confirmed.

Checking Your CAS for Errors

As soon as the CAS arrives, cross-check every field against your passport and offer documents. The most common errors are name spelling that does not match the passport, wrong date of birth, incorrect course dates, incorrect tuition fee totals, zero fees paid when a deposit has been made, and ATAS requirement incorrectly shown or omitted.

How to Request Corrections

Minor Corrections

For minor corrections such as a name variation or an incorrect fee figure, contact the institution’s immigration or admissions team with the specific error and a copy of the relevant passport page. The institution can typically update the Sponsor Management System record without reissuing the CAS number. Request written confirmation before submitting the visa.

Substantial Corrections Requiring a New CAS

If the error is substantial, such as an incorrect course, wrong qualification level, or personal details significantly mismatching the passport, the institution may need to withdraw the CAS and issue a new one. Do not submit the visa application until the institution has confirmed the corrected record in writing.

If the Institution Refuses to Issue a CAS

Reasons an Institution May Refuse

An institution may decline to issue a CAS if you have outstanding tuition fee debts from a previous programme, cannot demonstrate academic progression from prior UK studies, if the course does not meet Student Route requirements, or if your previous UK immigration history raises concerns under the institution’s sponsor duties.

If Problems Cannot Be Resolved

The CAS refused what to do UK situation has a defined process: consult the institution’s immigration team first, then a qualified UK immigration solicitor if the refusal cannot be resolved internally. Some students assess whether an alternative UK institution can sponsor them; others evaluate whether a different study destination is more viable.

If you are weighing options beyond the UK, the Apply to Another Country After Visa Rejection: Complete Guide covers alternative study destinations and the steps involved in redirecting your application.

CAS Expiry and When You Need a New CAS Number

Understanding the CAS expiry student visa UK rules from the moment the record arrives eliminates one of the most common sources of preventable application delays.

How Long a CAS Is Valid

A CAS is valid for 6 months from the date the institution issued it. The CAS validity period UK student visa clock runs from the issue date on the statement, not from the date you received the email or the date your course starts. If the 6 months pass before you apply, the CAS expires and a new one must be requested. Note the issue date immediately, calculate the deadline, and submit the visa application before that date. If the CAS expires, the institution must generate a new record and the six-month clock restarts from the new issue date.

CAS for Visa Extension Applicants

Students already in the UK who need to extend their leave or begin a new programme need a new CAS number needed UK visa from their institution for the extension application. The new CAS must reflect the remaining programme duration or the new programme details. The 6-month validity rule and academic progression requirements apply to extension CAS numbers in the same way as initial entry CAS numbers.

Students nearing the end of their programme should review the UK Graduate Route 2026: Application Guide, Eligibility and Costs to understand the post-study pathway that follows a UK degree.

CAS for Pre-Sessional English and Combined Programmes

Some UK institutions issue a single combined CAS covering both a pre-sessional English programme and the main degree, but only when the student has fully met the English requirements and holds confirmed offers for both stages. Other institutions issue separate CAS numbers for each stage. The approach used affects whether one visa application or two are required. Confirm the institution’s policy before the CAS window opens.

Academic Progression and the 5-Year Study Limit for CAS Eligibility

Academic progression CAS UK requirements and the 5-year study limit determine whether the institution is permitted to issue a CAS at all for students who have previously held a UK student visa.

The Academic Progression Requirement

Who It Applies To

Students who have previously held a UK Student visa, or the older Tier 4 visa, are subject to the academic progression requirement. Before issuing a new CAS, the institution must assess that the new programme represents genuine academic progress from the student’s previous UK studies. This assessment is part of the institution’s UKVI sponsor obligations.

What Academic Progression Means

Academic progression typically means the new programme is at a higher RQF level than the previous UK programme: a bachelor’s graduate moving to a master’s, or a master’s graduate moving to a PhD. Applying for a second bachelor’s degree after completing the first does not typically satisfy the requirement, and the institution may decline to issue the CAS.

Exceptions to Academic Progression

An institution may in exceptional circumstances issue a CAS for a programme at the same level if the new course is a direct continuation or deeper specialisation of the previous one, or if the two programmes together support a clear career outcome neither could achieve alone. The institution assesses this case by case. No exception is automatic.

The 5-Year Study Limit

How the Limit Works

The 5 year study limit UK student visa rule caps study at a maximum of 5 years under Student or Tier 4 visa status. This clock starts from your first UK student visa and includes all subsequent study periods regardless of gaps or changes of institution. Once the 5-year total is reached, the institution cannot issue a new CAS.

Exceptions to the 5-Year Limit

Students who completed a 4-year undergraduate degree are subject to a 6-year limit rather than 5. Students enrolled in postgraduate research programmes, including PhD, MPhil, and other UKVI-approved research qualifications, are not subject to any time limit. The 5-year clock includes time on old Tier 4 visas, not only current Student Route leave.

Tracking Study Time

If you have studied in the UK previously, confirm your remaining study time eligibility with the institution’s immigration team before accepting any new offer. Discovering at the CAS stage that the limit has been reached is a serious problem with no straightforward remedy.

Frequently Asked Questions About the UK CAS Number

What is a CAS number for a UK student visa?

A CAS number is a 14-character alphanumeric reference generated by UKVI‘s Sponsor Management System at your institution’s request. It is an electronic record, not a physical document. You enter the number in a dedicated field on the online application form, and UKVI officers retrieve the full sponsorship record from their database. The CAS confirms that a licensed UK institution has accepted you onto an eligible programme, a mandatory requirement for the Student Route. Without a valid CAS, the application cannot proceed regardless of any other documents provided.

How long does it take to receive a CAS number from a UK university?

Most institutions issue the CAS within 5 to 10 working days after all pre-conditions are met. Pre-conditions include an unconditional offer, any required deposit, and submission of all pre-CAS documents such as passport copy, qualifications, English language results, and ATAS certificate where applicable. If your course requires ATAS, allow several additional weeks before the CAS timeline can begin. If the CAS has not arrived within 10 working days, contact the institution’s international admissions or immigration team and confirm when each pre-condition was completed.

Can I apply for a UK student visa without a CAS number?

No. The CAS number is a mandatory requirement and the UKVI online application form cannot be completed without it. The CAS cannot be substituted by any other institutional document including the offer letter, acceptance email, or enrolment confirmation. These documents serve other purposes but do not satisfy the CAS requirement. Wait until the CAS is received before starting the visa application form. Beginning the form without the number serves no purpose, as the application cannot advance past the CAS entry field.

How many characters is a UK CAS number?

A UK CAS number is always 14 characters long and alphanumeric. The institution includes the number in the CAS statement email sent to your registered address. When entering it on the UKVI application form, type each character exactly as shown in the email. A single incorrect character prevents UKVI from locating the record and stalls the application. If the system returns an error, contact the institution immediately to confirm the exact reference. Do not attempt to correct the number by guessing.

My UK visa was refused. Do I need a new CAS number to reapply?

Yes. A visa refusal by UKVI means the CAS used in that application cannot be reused. A new CAS must be requested from the institution before reapplying. This differs from a rejection as invalid, where the application was returned unprocessed and the same CAS may still be usable if it has not expired. It also differs from a withdrawal, where the CAS may be reusable within the 6-month validity window. Confirm which outcome applies with your UKVI correspondence before requesting a new CAS.

What happens if my CAS number expires before I apply for my visa?

You must request a new CAS from the institution. The 6-month validity clock runs from the issue date on the CAS statement, not from the date you received the email or the course start date. Once expired, UKVI does not accept the reference as valid sponsorship evidence. Note the issue date as soon as the CAS arrives, calculate the expiry deadline, and submit the visa application before that date. Allowing the original CAS to lapse means requesting a replacement and restarting the processing timeline.

What does my UK CAS contain?

The CAS record contains your full name as it appears on your passport, date of birth, nationality, country of birth, and current passport number. It also contains the full course name, RQF qualification level, course start and end dates, total tuition fee for the programme, and the amount already paid to the institution. It records the qualifications the institution used to assess you as meeting entry requirements, whether ATAS clearance is required for your course, and the institution’s name and UKVI sponsor licence number.

Can I use the same CAS number if I withdraw and reapply for my UK student visa?

In most circumstances, yes. If you withdraw a visa application before UKVI makes a decision and the original CAS has not expired, it may still be usable within the 6-month validity window. Do not assume reuse is automatic: confirm with the institution’s immigration team before proceeding, as outcomes vary depending on withdrawal circumstances and the institution’s policies. If the CAS has expired or the institution advises it cannot be reused, a fresh CAS must be requested before submitting any new application.

What is academic progression for a UK student visa?

Academic progression is the requirement that students who have previously held a UK Student or Tier 4 visa must demonstrate that the new programme is a genuine step forward from their previous UK studies. This typically means studying at a higher RQF level: bachelor’s to master’s, or master’s to PhD. Institutions assess progression before issuing a CAS under their UKVI sponsor obligations. If progression cannot be demonstrated, the CAS may be refused. Exceptions exist where two programmes at the same level together support a clear career outcome, assessed individually by the institution.

I found an error on my CAS. What should I do?

Contact the institution’s international student immigration team or admissions office immediately and do not submit the visa application until the error is resolved. Identify the specific field affected and provide supporting evidence such as a passport copy for name or date of birth discrepancies. For minor corrections, the institution can typically update the Sponsor Management System without reissuing the CAS number. For substantial errors involving the course, qualification level, or significantly mismatched personal details, a new CAS may be required. Never submit to UKVI with a known error on the CAS record.

Disclaimer

The information in this guide reflects publicly available data from UK Visas and Immigration, the Home Office, and official UK university immigration offices as of 2026 and is provided for general informational purposes only. CAS issuance requirements, academic progression rules, the 5-year study limit, ATAS requirements, and UKVI processing procedures are subject to change by the Home Office without notice. Always verify current requirements at gov.uk/student-visa and with your institution’s international student immigration team before submitting any application. VisaToCampus does not provide immigration legal advice.