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Knowledge of language and life in the UK wrote:A person who successfully made an ILR application on the basis of a B1 level qualification can meet the English language requirement for naturalisation without needing to pass another qualification.

Applications made on or after 12 November 2015
For naturalisation applications made on or after 12 November 2015 and settlement applications made on or after 19 November 2015, the only tests that are acceptable are qualifications covering speaking and listening at B1 or above from the Secure English Language Test (SELT) list in the Immigration Rules, Appendix O. No other tests are acceptable. The test must be taken at an approved test centre – see link for list of approved test centres.

The test must have been taken no more than 2 years before the date of application.

However, for settlement applications, you must accept a qualification from one of the providers on the current SELT that has passed the expiry date, if it has previously been accepted by us in connection with another immigration application, e.g. for entry clearance. A qualification that is not from one of the providers on the current SELT list is not acceptable even if previously accepted by us in connection with another application.

For citizenship applications a person does not need to pass another English language test if they met the English language requirement for settlement by passing a B1 level test.

Applicants do not need to supply any evidence - instead they must provide a unique reference number (URN).