As you browse for suitable courses, you’ll come across many references to “accrediation”, “validation”, “recognised”, etc. What’s the difference and what does it matter? As with much else, the important thing is to do your research. Depending on the market that you want to teach in, accreditation will be vital or irrelevant. As a general rule, the more unsatisfied demand that exists in the country for TEFL teachers, the less you’ll need an accredited qualification.
Be aware that TEFL is generally an unregulated industry in most places, meaning anyone can set up a course and sell it. The same goes for an accreditation body: anyone can offer accreditation or validation of TEFL courses. So the important thing is the reputation of the validating body in the place you want to teach.
Perhaps it’s too obvious to mention, but if you want the most flexibility in where you can teach (i.e. you know you want to teach EFL, but don’t know where), go for the most respected and globally recognised qualification.
If you are certain you want to teach in one particular country (due to a relationship, for example), then by all means look only at the local reputation of schools or accreditation organisations. However, circumstances change, and one of the great things about becoming a TEFL teacher is the option to teach anywhere in the world.
If you opt to go for an unaccredited or weakly-accredited course, have it clear in your mind that your employability is closely connected to the reputation of this individual school. Make sure the price of the course reflects this.
Also be aware that many trainees on highly-respected, accredited courses like the Trinity Cert TESOL and the Cambridge CELTA have, in fact, done some form of TEFL training before, but have found it either inadequte for their needs or unable to secure them the teaching job they desire.