The 30-second version
A COI (Certificate of Insurance) is a document from a moving company's insurer showing specified coverage. Many managed, doorman, elevator, and commercial buildings require one before a move. The exact certificate holder, additional-insured wording, limits, submission method, and deadline come from each building's management, so ask both the origin and destination.
How to get one (it's the mover's job)
The moving company's insurance representative issues the certificate. Your job is to get the requirements from each building's managing agent: exact legal names, requested coverage, certificate-holder and additional-insured wording, submission method, and deadline. Forward the instructions to the mover and wait for written building approval before treating the paperwork as complete. Processing time and any administrative charge vary by mover, insurer, and building.
Red flags
Ask early whether the mover can satisfy the building's exact requirements and who will submit the certificate. A certificate is not a substitute for verifying the mover itself: get the company's legal name and authority number, confirm the record with the appropriate regulator, and review the written estimate and insurance terms.
Timeline
Ask your managing agent for COI requirements as soon as you have a move date. Most buildings want the certificate on file 24–72 hours before the move, and some tie it to the service-elevator reservation — no COI on file, no elevator slot. Handle it a week out and it's paperwork; handle it move-day morning and it's a crisis.