What qualifications do I actually need to teach English online?

There is no universal credential requirement for teaching English online as an independent tutor. What actually matters, in roughly decreasing order:

• A TEFL or TESOL certificate. 120 hours is the commonly accepted minimum. Reputable providers include International TEFL Academy, Bridge, and i-to-i. Helpful with parents who are shopping by credentials, and often required by agencies.
• Near-native or native English proficiency. Many parents (rightly or not) select on accent.
• A bachelor's degree. Required by many agency platforms, but not required to run an independent tutoring business.
• Teaching, tutoring, or childcare experience. Sells well, especially to parents of young learners.
• A specialty. Exam prep (IELTS, TOEFL, Cambridge YLE), business English, phonics, or special-needs tutoring all command premium rates.

Independent tutors set their own bar. Many successful ones have a TEFL plus a year or two of tutoring experience and no formal teaching degree.