A 120-hour course is the standard minimum employers mention. Longer courses of 180 or 250 hours add content and sometimes a higher regulated level, but extra hours are worth paying for only if they come with something an employer values: assessed teaching practice, a named tutor, or a regulated qualification you can look up. Hours alone, without those, are a weak signal.
Why 120 hours became the benchmark
Cambridge's CELTA totals 120 hours, regulated by Ofqual at Level 5. A 2023 article by the Irish language-school association's communications officer described a standard TEFL certificate of 120 hours as the usual credential for ESL posts in Irish schools. A 2021 Maynooth University careers sheet describes the old ACELS-recognised course in similar terms: at least 120 hours, with 100 hours of course input and 20 of reflective learning, including at least six hours of classroom practice. The same sheet noted that private courses ranged from 20 to 140 hours and were mostly online with no integrated teaching practice.
So 120 became shorthand, but it hides a large difference: 120 hours including observed teaching with real learners is not the same product as 120 hours of online reading and quizzes.
What providers sell at each length
As of 19 October 2026, the providers we looked at published the following. These are the providers' own descriptions, not independent assessments.
| Length | Examples published | Regulation stated | What the page says is included |
|---|---|---|---|
| 120 hours | TEFL Institute of Ireland 120-hour course (€175); TEFL Academy Level 3 (€165) | Institute page calls it 'accredited' without naming the awarding body; Academy says Qualifi and Ofqual regulated | Tutor support or mentorship; no assessed practice in the base price |
| 168 to 180 hours | TEFL Institute of Ireland 180-hour Level 5 (€265); TEFL Academy 168-hour Level 5 (€265) | Both describe Level 5 Ofqual-regulated diplomas; the Institute names Highfield as awarding organisation, the Academy names Qualifi | Longer content; 6 months of access on the Institute's course; practice is a separate add-on |
| 250 to 300 hours | TEFL Institute of Ireland 300-hour (€375); The TEFL Org 250-hour (priced in £) | Institute's 300-hour is Ofqual regulated; The TEFL Org's 250-hour page says 'DEAC regulated' | More modules; The TEFL Org lists its 270 and 280-hour options with 20 or 30 classroom hours |
| CELTA (120 hours) | Delivered at approved centres | Ofqual, Level 5 | Assessed teaching practice with real learners |
| CertTESOL (130 guided hours, 200 total) | Delivered at approved centres | Ofqual, Level 5 | At least six hours of supervised teaching with real learners |
How hours are counted
Check what the headline number means. Cambridge and Trinity publish different measures for their qualifications: CELTA 120 hours in total, CertTESOL a minimum of 130 guided learning hours within a total qualification time of 200 hours. Commercial providers are not always so clear. Ask whether the figure is guided learning hours with a tutor, total study time, or a sum of module durations, and whether optional live classes are counted.
- Guided learning hours: time led or supervised by a tutor.
- Total qualification time: guided hours plus independent study.
- Course hours: often the provider's own estimate, and may include optional extras.
Which length fits which plan
- Teaching in a market that accepts a generic certificate: 120 hours with a named tutor and marked work may be enough. Ask the employer.
- Wanting a stronger CV without a classroom course: a regulated Level 5 diploma of 168 to 300 hours adds depth, but confirm the employer values the level. Some employers may not distinguish between 180 and 300.
- Targeting competitive schools or international schools: assessed teaching practice usually matters more than extra online hours. See TEFL vs CELTA.
- Wanting specialisms: short add-on modules in young learners, business English or online teaching can be taken after the main certificate. Our pages on young learners and business English explain when these help.
Practice hours and why they change the picture
Several of the longer courses we looked at include classroom hours. The TEFL Org lists 270 and 280-hour diplomas with 20 and 30 classroom hours, and The TEFL Academy sells a combined 168-hour course with 10 classroom hours in Dublin or Galway. The TEFL Institute of Ireland lists a separate 10-hour practicum. CELTA and CertTESOL build teaching practice into the qualification itself, with CertTESOL requiring at least six hours of supervised teaching with real learners. Teaching practice is where you learn to manage a class and receive feedback from an observer, which written work cannot replace. If you can only afford one upgrade, a modest amount of observed practice is often a better use of money than an extra 100 hours of online modules, provided the employer you are targeting values it.
A practical way to test any length claim is to ask for the module list and the assessment for each module. A genuine 180-hour course should be able to show you what is covered in the extra 60 hours, how it is marked and how many tutor-guided hours are included. Ask also how long you have access: the TEFL Institute of Ireland's pages list six months of access for all three of its main courses, while completion times are given as 2 to 4 weeks for 120 hours, 6 to 8 for 180 and 8 to 10 for 300. If a course states a duration much shorter than its hours would imply for someone studying part-time, ask how that is achieved.
Keep the written answers always. If a provider later changes the course content or its description of the hours, your emails are the evidence of what was promised when you paid.
Questions to ask before choosing a longer course
- What exactly are the extra hours: more assessed work, new modules, or longer access?
- Is the longer course the same qualification at a higher level, or a different product?
- Does the employer I want to work for ask for more than 120 hours? If not, I may be paying for nothing.
- Does it include any observed teaching, or only an optional add-on?
- What is the full price after promotion ends, and what is the refund policy?
The extra 60 to 130 hours between a 120-hour and a 250 to 300-hour course are worth paying for if they give you a regulated qualification you can verify, a stronger set of marked assignments, or a route to practice. If the main difference is length of reading material, the cheaper option may be enough. For a side-by-side look at providers, see TEFL courses in Ireland compared. We are an affiliate of the TEFL Institute of Ireland, whose 120, 180 and 300-hour options are listed above next to its competitors.
Want to see the TEFL Institute of Ireland's current courses and prices? Check them against the criteria on this page.
Compare TEFL coursesThis is an affiliate link. See our affiliate disclosure.Frequently asked questions
Do employers ask for more than 120 hours?
Most sources we read treat 120 hours as the usual minimum. Some employers ask for CELTA or assessed practice instead, so ask the employer.
What is the difference between guided hours and total hours?
Guided hours are tutor-led or supervised time. Total qualification time adds your independent study, as in Trinity's CertTESOL: 130 guided hours within 200 total.
Is a 300-hour course better than a 120-hour one?
Only if the extra hours bring a regulated qualification, more marked work or practice. Longer reading content alone may not change your job prospects.
Can I upgrade later?
Some providers sell top-up modules or practicum courses separately. Ask whether earlier fees count towards a higher course.