BMW does not publish a general position on length-adding seat belt extenders or offer a documented OEM extender that adds length to the seat belt.
Genuine BMW parts named "Seat Belt Extender" refer to a different device entirely: a motorized arm, found in some BMW coupes, that presents the seat belt to an occupant and retracts it afterward.
OEM seat belt extender available: ❌ No
General seat belt extender position: ⚠️ Not published
BMW's "Seat Belt Extender" Is Not a Length-Adding Device
Genuine BMW parts named "Seat Belt Extender" or "Seat Belt Extender Arm" exist for certain BMW coupes, including the 2 Series, 4 Series, M2, and M4. These are motorized presenter arms that move the seat belt forward so it is easier for an occupant to reach, then retract afterward. They do not add length to the seat belt.
Why Some BMW Users Look for Aftermarket Extenders
Public owner discussions show BMW users searching for length-adding aftermarket options despite the different meaning of "Seat Belt Extender" in BMW parts listings. In one discussion, a BMW i3 owner used an aftermarket extension to manage a hard-to-reach buckle related to limited hand mobility.
Aftermarket Options
If you determine that an aftermarket extender is the best option for you, ensure you select a seat belt extender by the exact make, model, year, seating position, and country of the vehicle.
Sources
Genuine BMW Parts: Seat Belt Extender – Left (72-11-7-352-851)