A megachurch is an American term for a church having 2,000 or more people in average weekend attendance.

Average weekly attendances are shown in parentheses:

1. Yoido Full Gospel Church, Seoul, South Korea (253,000)

2. Jotabeche Methodist P. Church, Santiago, Chile (150,000)

3. Calvary Temple, Hyderabad, India (120,000)

4. Deeper Life Bible Church, Lagos, Nigeria (120,000)

5. Elim Church, San Salvador, El Salvador (117,000)

6. Nambu Full Gospel, Seoul, South Korea (110,000)

7. AOG Grace and Truth, Kyanggi-do, South Korea (105,000)

8. Kum Ran Methodist, Seoul, South Korea (80,000)

9. Vision de Futuro, Santa Fe, Argentina (70,000)

10 Ondas del Luz, Buenos Aires, Argentina (70,000)

11. Victory Christian Fellowship, Philippines (110,000)

12. Christ's Commission Fellowship (60,000)

13. Young Nak Presbyterian Church, South Korea (60,000)

14. Winners Chapel, Ota, Nigeria (50,000)

15. Soong Eui Methodist, Inchon, South Korea
(47,000)

16. Lakewood Church, Houston, Texas (45,000)

https://en.m.wikipedia.org/wiki/Megachurch

What of the Roman Catholic Basilica in Rome?

And winner's chapel has been lying to us all these years that they have the world's largest church auditorium

What of list of Mega Churches In United States