TEFL Certified  ·  Native English Speaker  ·  5/5 Stars

Master English With Confidence

Personalized lessons tailored to your goals; whether it's acing exams, advancing your career, or speaking fluently in everyday life.

2,654
Lessons Taught
461+
Students Taught
About me

Passionate About Teaching English

Experience/Qualifications:

TEFL Certified
10 years of teaching experience
Thousands of lessons taught
Hundreds of students taught
Native English speaker
5/5 star average rating from students

Hello, I’m Gareth O’Sullivan, a 26-year-old EFL teacher from New York, now based in Ireland. With over ten years of experience teaching English as a foreign language, I’ve had the privilege of helping students from all over the world achieve their goals—and I’ve loved every step of the journey.

My teaching career began with tutoring international students across a range of subjects. Seeing their progress and confidence grow inspired me to pursue English teaching full-time. From there, I moved into online teaching, building a strong reputation and loyal student base on platforms like Cambly and Italki.
On Italki, I developed my teaching style further and became one of the platform’s highest-rated English teachers, earning a consistent five-star rating and dozens of positive reviews. After delivering thousands of lessons and working with hundreds of satisfied students, I decided in 2025 to take the next step—launching my own website and teaching independently.

Today, I focus on providing high-quality, personalised lessons designed to help you reach your English goals as efficiently and confidently as possible—whether that’s improving your speaking skills, preparing for exams, or advancing your career.

If you’re ready to take your English to the next level, I’d love to work with you.

Thank you.

Mr. Gareth O’Sullivan

Lesson

Find the Right Lesson/Course for You

Choose from a variety of English courses designed to match your goals, level, and schedule.

Browse Courses

Conversational English

Created for students who need more speaking practice, focusing on topical discussions in a relaxed setting, with corrections and guidance on pronunciation, grammar, and vocabulary to help build fluency and confidence.

Level - A1-C2
60min
5
€20

General English

Designed to improve your overall spoken English skills, with additional focus on listening and reading through the analysis of articles and pieces of text, as well as targeted grammar improvement, helping you build confidence in real-life communication.

Level - A1-C2
60min
5
€30

Speaking exam preparation

Ielts, Toefl, Toeic

Speaking exam preparation for IELTS, TOEFL, TOEIC, and other exams, focusing on practical training through mock exams, with in-depth corrections in grammar, pronunciation, and vocabulary to help you achieve your target score or improve on a previous result.

Level - A1-C2
60min
5
€35

Business English

For students seeking to strengthen their professional communication, with practical support for job interviews, meetings, and career advancement, tailored to suit your specific profession and field, helping you succeed in the workplace.

Level - A1-C2
60min
5
€50

Conversational English

Created for students who need more speaking practice, focusing on topical discussions in a relaxed setting, with corrections and guidance on pronunciation, grammar, and vocabulary to help build fluency and confidence.

Level - A1-C2
60min
5
€80

General English

Designed to improve your overall spoken English skills, with additional focus on listening and reading through the analysis of articles and pieces of text, as well as targeted grammar improvement, helping you build confidence in real-life communication.

Level - A1-C2
60min
5
€120

Speaking exam preparation

Ielts, Toefl, Toeic

Speaking exam preparation for IELTS, TOEFL, TOEIC, and other exams, focusing on practical training through mock exams, with in-depth corrections in grammar, pronunciation, and vocabulary to help you achieve your target score or improve on a previous result.

Level - A1-C2
60min
5

Business English

For students seeking to strengthen their professional communication, with practical support for job interviews, meetings, and career advancement, tailored to suit your specific profession and field, helping you succeed in the workplace.

Level - A1-C2
60min
5
€200

Conversational English

Created for students who need more speaking practice, focusing on topical discussions in a relaxed setting, with corrections and guidance on pronunciation, grammar, and vocabulary to help build fluency and confidence.

Level - A1-C2
60min
5
€160

General English

Designed to improve your overall spoken English skills, with additional focus on listening and reading through the analysis of articles and pieces of text, as well as targeted grammar improvement, helping you build confidence in real-life communication.

Level - A1-C2
60min
5
€240

Speaking exam preparation

Ielts, Toefl, Toeic

Speaking exam preparation for IELTS, TOEFL, TOEIC, and other exams, focusing on practical training through mock exams, with in-depth corrections in grammar, pronunciation, and vocabulary to help you achieve your target score or improve on a previous result.

Level - A1-C2
60min
5
€280

Business English

For students seeking to strengthen their professional communication, with practical support for job interviews, meetings, and career advancement, tailored to suit your specific profession and field, helping you succeed in the workplace.

Level - A1-C2
60min
5
€400
Book Now

Contact Teacher Form

Have a question or ready to start learning? Send me a message or book a trial lesson.

€5
30 minute trial lesson
Book now
Phone Number
(+353) 874211702
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Language Levels

Which Level Are You?

All courses are tailored to the Common European Framework of Reference for Languages (CEFR). Not sure of your level? Your trial lesson includes a quick assessment.

A1
Beginner
Can understand and use basic everyday expressions
A2
Elementary
Can communicate in simple, routine tasks
Basic Users
B1
Intermediate
Can deal with most travel and work situations
B2
Upper Intermediate
Can interact with fluency and spontaneity
Basic Independent Users
C1
Advanced
Can express ideas fluently and spontaneously
C2
Mastery
Can understand virtually everything heard or read
Independent Users
Experience

Work Experience

A proven track record in English language education across multiple institutions.

English as a Foreign Language Teacher

Italki.com
2021 – 2025
Prague, Czech Republic

Became one of the highest rated English teachers on the platform, achieving a five star rating and dozens of positive reviews from students worldwide. Taught thousands of lessons and helped hundreds of students reach their language goals before transitioning to full independence in 2025.

English as a Foreign Language Teacher

Cambly.com
2020 – 2021
Prague, Czech Republic

Built a strong reputation and solid student base in a short time, earning consistently positive feedback and establishing the foundation for continued growth on Italki.

2016 – 2020
Killarney, Ireland

Provided one-to-one language tutoring for foreign exchange students across multiple subjects. The satisfaction gained from helping students achieve their goals inspired a full-time career in English language teaching.

Testimonials

Students Reviews

See what previous students has to say about the service I provided

Gareth is great and professional teacher, who can help you not only with improving conversational skills but also with grammar. He helped me to improve IELTS speaking score by 1 point (from 5.5 to 6.5) in just 3 lessons!

Artem Davydov
Aug 17, 2023
9 English lessons

Great and interesting teacher! The lesson was fun, and Gareth is very good at finding common interests to speak about. My English confidence has already improved!

Seb
Jan 15, 2024
9 English lessons

I believe he is the best teacher on the platform. He has helped me greatly in improving my English, and he is a highly professional individual. Highly recommended.

Oscar Orduz
Jun 6, 2023
31 English lessons

How can a class be that much fun? Learning with Gareth is a total different, unique and exciting experience. Always striving for better. Much appreciated

Bashayer Khan
May 17, 2022
13 English lessons

Was a very good learning experience. I would love to keep on a long term English learning plan with Gareth the class was totally different from the classes I used to take in the past. It was efficient and fun. Just 60 mins, I
feel my improvement already

Georgina
Apr 19, 2024
9 English lessons

I recently completed a spoken English class with Gareth, and I must say, he's an exceptional instructor. His kindness and patience truly stand out, creating a
welcoming and supportive learning environment.

Stella
Feb 22, 2024
3 English lessons
Certificate & Achievement

Our Certificate & Achievement

Choose from a variety of English courses designed to match your goals, level, and schedule.
Dive deep into the complexities of English grammar to refine your understanding and application for effective communication.
2020

120 Hour Premier TEFL Course

Build confidence in everyday conversations with practical speaking exercises and real-world scenarios.
2020

CELTA (Certificate in Teaching English)

Enhance your writing abilities with a focus on structure, style, and clarity, tailored for professional contexts.
2020

MA in Applied Linguistics

Dive deep into the complexities of English grammar to refine your understanding and application for effective communication.
2020