The difference between TESOL, TEFL, TESL and CELTA certificates

Confused about which certification to get? Don’t know what any of these acronyms mean? We demystify it all in this article!

Want to skip all the in depth information and just look at the bottom line? Scroll down to the bottom! If you want some detailed information, read on.

So what is the difference between TEFL, TESL, TESOL, and CELTA courses? First let’s look at what they are and then explore some differences.

  • TEFL (Teaching English as a Foreign Language) course: This prepares teachers to teach English in a country where English is not the primary language. For example, John from the USA goes to China to teach English.
  • TESL (Teaching English as a Second Language) course: This on the other hand would prepare a teacher to teach in an English speaking country to students whose first language isn’t English. For example, John from the USA stays in the USA and teaches English to students who want to learn English.
  • TESOL (Teaching English to Speakers of Other Languages) course: This encompasses both TEFL and TESL and can mean either one or both. Basically this prepares a teacher to teach a student whose native language isn’t English. For example, our good friend John from the USA is teaching a student who didn’t learn English as their first language.

Now that you understand those three, understand that they are often used interchangeably. That’s right, even though they all mean different things some people use them all the same way. I for one am definitely guilty of this. TESOL and TEFL are the most popular terms when talking about teacher training courses but TESL gets some use as well. Some people stick to the rules though and use them according to their actual meanings. For our purposes we are going to lump them all together and call them TESOL. What’s that I hear you say? What about CELTA?

  • CELTA (Certificate in Teaching English to Speakers of Other Languages) course: This is a specific brand of TESOL course operating under the umbrella of Cambridge University. You can think of TESOL as the type of product and CELTA as a specific brand. The CELTA course is the best known and some consider it the most respected of TESOL courses.

Basically for better or for worse CELTA is the industry standard because the quality of instruction doesn’t vary a huge amount, Cambridge is very well known, and it is generally well respected. There are other well known and respected TESOL courses as well (Trinity TESOL or SIT TESOL) but CELTA is by far the most internationally well known accreditation. There are literally thousands of other TESOL courses, and I’m not saying that all other TESOL courses are bad. In fact, some would consider many TESOL courses to be superior to the CELTA course. The problem is that because there are so many other TESOL courses there is a lot of variability in quality and price. So let’s break it down a bit.


Awarded by Cambridge ESOL

Course Length:
Full time course: 4 to 5 weeksPart time course: several weeks to several months

Varies greatly but around 1,500 to 3,500 USD

Over 18 and an adequate level of English proficiency (usually determined by a test and phone interview) is required to take the course

Course work:
6 hours of assessed teaching practice with real EFL classes at two levels of ability

4 written assignments: one focusing on adult learning; one on the language system of English; one on language skills; and one on classroom teaching. Each one is pass/fail

To be awarded the certificate you must pass both components the assessed teaching practice and the written assignments of which the teaching practice holds more weight (and yes lots of people do fail the course)

Quality control:
Each course is audited by an external assessor to maintain a constant standard of teaching

  • Trinity TESOL is a not as well known but is considered to roughly equal to CELTA.
  • SIT (School for International Training) TESOL is also well respected but even less common than the Trinity TESOL


Some accredited by proper institutions others not

Course length:
Varies greatly some as short as a week some as long as several months but most respected TESOL courses are 100+ hours of instruction

Also varies greatly 200 to 4,000 USD, but generally less expensive than the CELTA

Depends completely on the school issuing the TESOL certificate

Course work:
Varies tremendously with some courses being only easy online work to some that require hours and hours of grueling work and include practical training in a real class but as a VERY general rule of thumb the course work is usually easier than the CELTA course work

Quality control:
Once again it is completely dependent on the school. Some are very rigorous some aren’t.

The bottom line is:
  • Go with the CELTA TESOL certificate if you want to have the best chance of getting your certificate recognized by the majority of potential employers and money/time isn’t a big consideration.
  • Go with another TESOL certificate if you want a cheaper/easier/shorter option than CELTA, are looking for even better quality/more instruction, or if you want to be taught a specific teaching methodology.