When determining the small benefit cash-out amount in a DB contributory plan are employee contributions part of the vested accrued benefit. If not, could you direct me to the Code site.

Yes, they are a part of the accrued benefit that is used to determine if the limit is exceeded. There is no distinction in the law between employer-derived benefit and employee-derived benefit for this purpose.

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In the U.S., most of the contributory DB plans are sponsored by a governmental organization. If that is the case here, please use caution in applying the Code.