The UK student visa: CAS, ATAS, and the Graduate Route
How to convert a CAS into a Student visa, when ATAS applies, and what the two-year Graduate Route unlocks.
The UK visa system is well-documented but front-loaded with acronyms. Here is the plain-English version of what you actually file.
The CAS is the trigger
A Confirmation of Acceptance for Studies (CAS) is a 14-digit reference number your university issues after you accept an unconditional offer and pay a tuition deposit (typically £2,000–£5,000). You cannot file a Student visa without it. CAS letters expire after 6 months, so time your visa application inside that window.
The ATAS certificate
If your masters is in a sensitive research area — advanced physics, aerospace, nuclear engineering, certain AI/ML tracks — you need an Academic Technology Approval Scheme (ATAS) certificate before you apply for the visa. Free, issued by the UK Foreign Office in 4–8 weeks. Your admission letter will explicitly say if you need it.
The visa itself
Fee: £490 (from outside the UK). Immigration Health Surcharge (IHS): £776/year, paid upfront for the full course duration. Financial proof: 9 months of living costs at £1,483/month if studying in London, £1,136/month elsewhere — money must sit in your (or a parent's) account for 28 consecutive days before you apply.
Processing: 3 weeks standard, 5 working days priority (+£500), 24 hours super-priority (+£1,000).
The Graduate Route (what makes UK worth it)
On graduation you get 2 years of unconditional work rights — 3 years for PhDs — with no salary threshold and no sponsorship required. This is the single most important post-study visa in Europe if you want optionality.
During those 2 years you can apply for a Skilled Worker visa once you hit £38,700 (or £30,960 in shortage occupations). Skilled Worker time counts toward Indefinite Leave to Remain — 5 years total for permanent status.
Common mistakes
Applying with fewer than 28 clear days of funds, using a joint account that is not in your name, letting your CAS expire, and forgetting to pay the IHS in the same session as the visa fee. The IHS is the number one reason applications get returned for correction.
