Do I need a TIMS card for Everest Base Camp?
Short answer
No, the EBC route does not use TIMS. You need a Sagarmatha National Park permit and the Khumbu Pasanglhamu Rural Municipality fee.
— Detail
TIMS is a Nepal Tourism Board card used for non-protected trekking corridors. EBC sits inside Sagarmatha National Park, which has its own permit (NPR 3,000 for foreigners) plus a NPR 2,000 local fee paid at Lukla. Both are collected at checkpoints — bring cash.
Sources
DNPWCKhumbu Pasanglhamu Rural Municipality