It depends on what course you want to do and where you want to do it! Most undergraduate courses in UK universities require overseas students to have an IELTS level of 6. You can see how this is equivalent to other examinations in this table:
TOEFL (Paper) TOEFL Computer TOEFL iBT IELTS
600 250 100 7
575 232 90 - 91 6.5
550 213 79 - 80 6
525 196 69 - 70 5.5
500 173 59 - 60 5
475 152 49 - 50 4.5
(Adapted from http://www.sheffield.ac.uk/eltc/useful/toefl_ielts.htm)
Here are some English language requirements for various university courses:
- Undergraduate BA (Hons) in Business Studies Bournemouth University (UK): 6.0
- MBA Bournemouth University (UK): IELTS: 6.5
- The Sheffield MBA (Sheffield University, UK): IELTS 7.0 with at least 6.0 in each component
- Undergraduate degree in Teaching English to Speakers of Other Languages at Wolverhampton University, (UK): IELTS 7.0
- Law at University of California Los Angeles (USA): TOEFL (paper) 600
It is important that YOU know what your level of English is. Be careful of other people promising you things about your level of English. Universities, colleges, language schools and agents all want your money! Students can be sold courses which are not suitable for them, and institutions sometimes make promises about how quickly you can improve your English. It is generally believed that the average student needs to study full time for three months to raise their IELTS result by one band. Of course, everyone is different and it may take you longer. If your level of English is less than 5.0 you should be aware that you still need to make substantial improvement in your English before you can successfully study at university!