What Does an ATTOMID of All 9s (e.g., 999999999) Mean?

Last updated: July 30, 2026

Overview

An ATTOMID populated with all 9s (for example, 999999999) indicates that the record could not be matched to a parcel or property record in ATTOM's assessor database at the time it was processed.

These records represent valid transactions but remain unmatched at the property level.

Details

An ATTOMID of all 9s is assigned when a transaction record cannot be confidently linked to a property in the assessor database.

Common reasons include:

  • The address or parcel information cannot be fully standardized.

  • The property is new construction or was recently created and is not yet reflected in assessor data.

  • The recorded document lacks sufficient parcel identifiers.

  • The parcel data is incomplete, conflicting, or formatted inconsistently.

ATTOM continuously attempts to rematch these records as updated assessor data becomes available. If a match is identified later, the record will be updated with a standard ATTOMID.

Important Notes

  • An ATTOMID of all 9s does not mean the transaction is invalid.

  • It does not mean the record is corrupt.

  • It does not mean the property does not exist.

  • It does not mean the record should be excluded from transaction-level analysis.

This status only indicates that a property-level match was not available at the time the record was processed.

Integration Guidance

  • Treat records with an ATTOMID of all 9s as standalone transaction records.

  • Do not use these records to join transaction data to property-level ATTOM datasets.

  • If property linkage is required, downstream processes should account for unmatched records.