An explanation of IELTS Band Scores

There is no pass or fail mark in IELTS.  The scores depend on the institutions you are applying to or for the respective countries immigration entry requirements. IELTS is scored on a nine-band scale, with each band score corresponding to a specified ability in English. Overall Band Scores are given to the nearest half band.
 

The band scores range from 0 (“did not attempt the test”) to 9 (“expert user”).

The following rounding conversion applies: if the average across the four skills ends in .25, it is rounded up to the next half band, (i.e. 6.25 = 6.5) and if it ends in .75 (i.e. 6.75 = 7.0), it is rounded up to the next whole band. Examples below:

If  you get:

6.5   Listening 6.5   Reading 5.0   Writing 7.0   Speaking 25    raw score

an Overall Band Score would be of 6.5 (25 ÷ 4 = 6.25 = Band 6.5).
                                 
If  you get:

4.0    Listening 3.5    Reading 4.0    Writing 4.0    Speaking 15.5  raw score

an Overall Band Score would be of 4.0 (15.5 ÷ 4 = 3.875 = Band 4.0).

BUT, if you get:

6.5      Listening 6.5      Reading 5.5      Writing 6.0      Speaking 6.125  raw score

 an Overall Band Score would be of 6.0 (24.5 ÷ 4 = 6.125 = Band 6.0).

The nine bands are described below:

9	Expert User	Has full operational command of the language: appropriate, accurate and fluent with complete understanding.
8	Very Good User	Has full operational command of the language with only occasional unsystematic inaccuracies and inappropriacies. Misunderstandings may occur in unfamiliar situations. Handles complex detailed argumentation well.
7	Good User	Has operational command of the language, though with occasional inaccuracies, inappropriateness and misunderstandings in some situations. Generally handles complex language well and understands detailed reasoning.
6	Competent User	Has generally effective command of the language despite some inaccuracies, inappropriacies and misunderstandings. Can use and understand fairly complex language, particularly in familiar situations.
5	Modest user	Has partial command of the language, coping with overall meaning in most situations, though is likely to make many mistakes. Should be able to handle basic communication in own field.
4	Limited User	Basic competence is limited to familiar situations. Has frequent problems in using complex language.
3	Extremely Limited User	Conveys and understands only general meaning in very familiar situations.
2	Intermittent	No real communication is possible except for the most basic information using isolated words or short formulae in familiar situations and to meet immediate needs.
1	User	Essentially has no ability to use the language beyond possibly a few isolated words.
0	Non User	Did not attempt the test.  No assessable information provided at all.

A 6.5 IELTS score lies roughly between B2 and C1 levels of the Common European Framework of Reference for Languages and >8 scores are C2.