401(k) recordkeepers by payroll integration depth

No entries assessed yet, and that is the finding. Recordkeepers publish payroll-integration lists as marketing, but none assessed so far publishes the field-level contract this index requires: which payroll systems get 180-degree versus 360-degree treatment, what a 360-degree write actually sets, and by what method.

The distinction itself is well documented by third parties. A 180-degree integration is one-way, pushing contribution and census data from payroll to the recordkeeper. A 360-degree integration adds the return trip, sending deferral-rate elections made on the recordkeeper platform back into payroll — without which every election change needs a manual step before the next payroll run. Publishing which recordkeeper does which, per payroll system, is the matrix nobody publishes, and populating it needs practitioner reporting rather than documentation.