From 22 February 2010, anyone who applies to study in the UK under Tier 4 of the points-based system must have a Confirmation of Acceptance for Studies (CAS) from their prospective sponsor (educational institution).

UK Border Agency will accept applications that are supported solely by visa letters if they have been lodged and paid for on or before 21 February 2010.  Any applications that are paid for on or after 22 February 2010 and are not supported by a Confirmation of Acceptance for Studies will be refused.

For more information, please see the UK Visas website here.