Western Alliance (WAL) in Phoenix is looking to raise $100 million.
The $9.7 billion-asset company said in a regulatory filing Wednesday that it could sell the stock from time to time through Credit Suisse Securities.
Western Alliance said it could use proceeds for a range of purposes, including capital injections into its bank.
The company has nine branches in the southwest United States. It operates Alliance Bank of Arizona, Bank of Nevada, First Independent Bank, Torrey Pines Bank and Western Alliance Equipment Finance.