The International English Language Testing System, or IELTS, is an international standardized test of English language proficiency for non-native English language speakers. It is jointly managed by the British Council, IDP, IELTS Australia and Cambridge Assessment English, and was established in 1989. IELTS is one of the major English-language tests in the world, others being the TOEFL, TOEIC, PTE:A, and OPI/OPIc.

IELTS is accepted by most Australian, British, Canadian and New Zealand academic institutions, by over 3,000 academic institutions in the United States, and by various professional organizations across the world.

IELTS is the only Secure English Language Test approved by UK Visas and Immigration (UKVI) for visa customers applying both outside and inside the UK. It also meets requirement for immigration to Australia, where TOEFL and Pearson Test of English Academic are also accepted, and New Zealand. In Canada, IELTS, TEF, or CELPIP are accepted by the immigration authority.

In 2017, over 3 million tests were taken in more than 140 countries, up from 2 million tests in 2012, 1.7 million tests in 2011 and 1.4 million tests in 2009. In 2007, IELTS administered more than one million tests in a single 12-month period for the first time ever, making it the world’s most popular English language test for higher education and immigration.