Union Bank and Trust
| Status: | Inactive as of 07/21/1988 |
| Absorption - Assisted | |
| Successor Bank: | WestStar Bank |
| Headquarters: | Union Bank and Trust 100 East Frank Phillips Boulevard Bartlesville, OK 74003 |
| Established: | 10/01/1909 |
| FDIC Insurance: | 01/01/1934 |
| FDIC Cert: | #4040 |
| Charter Class: | Commercial bank, state charter and Fed nonmember, supervised by the FDIC |
| Total Assets: | $115,430,000 |
| Total Deposits: | $128,969,000 |
History
| 1909-10-01 | Institution established: Original name:The Union National Bank of Bartlesville | |
| 1975-02-20 | Changed name to Union Bank and Trust | |
| 1984-03-01 | Acquired The Dewey Bank (4079) in DEWEY, OK | |
| 1988-07-21 | Failed. Acquired with government financial assistance and subsequently operated as part of First National Bank in Bartlesville (4039) | |
| 1988-08-01 | Changed name to WestStar Bank, a National Association (4039) | |
| 1990-12-14 | Acquired Peoples Federal Savings Association (32937) in BARTLESVILLE, OK | |
| 1993-04-01 | Changed primary regulatory agency from COMPTROLLER OF THE CURRENCY to FEDERAL RESERVE BOARD | |
| 1993-04-01 | Changed name to WestStar Bank (4039) | |
| 1998-04-01 | Acquired Victory Bank of Nowata (16463) in NOWATA, OK | |
| 2002-04-18 | Acquired WestStar Bank (4039) in BARTLESVILLE, OK | |
| 2002-04-18 | Acquired Arvest State Bank (25661) in TULSA, OK | |
| 2002-04-18 | Merged into and subsequently operated as part of Arvest Bank (8728) in FAYETTEVILLE, AR | |
| 2002-05-16 | Acquired Arvest Bank (26867) in NORMAN, OK | |
| 2002-05-16 | Acquired Arvest Bank (13595) in SHAWNEE, OK | |
| 2002-05-16 | Acquired Arvest Bank (4081) in DUNCAN, OK | |
| 2002-06-13 | Acquired Arvest Bank (3891) in ROGERS, AR | |
| 2003-07-01 | Acquired The Bank of Yellville (16354) in YELLVILLE, AR | |
| 2003-12-05 | Acquired Superior Bank, FSB (28958) in FORT SMITH, AR | |
| 2007-01-05 | Acquired The Caney Valley National Bank (4633) in CANEY, KS | |
| 2009-12-11 | Acquired SolutionsBank (4731) in OVERLAND PARK, KS as part of a government assisted transaction. | |
| 2012-01-25 | Reorganized. | |
| 2013-03-29 | Acquired Arvest Trust Company, National Association (33148) in ROGERS, AR | |
| 2013-12-07 | Acquired National Bank of Arkansas in North Little Rock (23331) in NORTH LITTLE ROCK, AR | |
| 2018-04-21 | Acquired Bear State Bank (3857) in LITTLE ROCK, AR |