| Relationships | Role | Relationship Start | Relationship End |
| National Bancshares Corporation Of Texas | Parent | 9/5/1980 | 9/29/1987 |
| Main Plaza Corporation | Parent | 5/7/1973 | 12/24/1974 |
| Cullen/Frost Bankers, Inc. | Parent | 12/31/1970 | 5/6/1973 |
| Cullen/Frost Bankers, Inc. | Parent | 1/7/1969 | 12/30/1970 |
| Acquisitions & Mergers | Role | Assets | Acct Method | Type | Transaction Date |
| Nbc Bank - San Antonio, National Association | Buyer | 938,232 | Discontinued | 9/30/1987 |