Prosperity Bank Routing Number - 40 Acquisitions and the Routing Numbers They Left Behind

A forty-year acquisition machine

Prosperity Bancshares was founded in 1983 in Edna, Texas — a town of 5,000 people about 100 miles southwest of Houston. Founder David Zalman started with a single community bank and a strategy that hasn't changed in four decades: find well-run community banks in Texas, buy them at reasonable prices, cut costs through operational integration, and repeat. Over 40 acquisitions later, Prosperity has grown from a tiny rural bank into one of the largest banking organizations in Texas with roughly $40 billion in assets.

Routing number

Prosperity's primary routing number is 113122655. The 113 prefix ties to the Federal Reserve Bank of Dallas. For wire transfers, 113122655 applies regardless of which institution your account originated from. For incoming international wires, the SWIFT code is PROBUSB1.

If your account was opened directly with Prosperity, 113122655 is your number. If your account originated at an acquired institution — LegacyTexas, Guaranty Federal, First Federal, Tradition Bank, or dozens of others — your routing number may be different. Log into Prosperity's online banking to confirm, or look at the bottom-left corner of your most recent Prosperity-branded check.

How acquisitions create routing number complexity

When Prosperity acquires a bank, it doesn't immediately migrate all accounts to 113122655. Legacy accounts continue functioning with their old routing numbers — sometimes for years — while new accounts open under the Prosperity number. The Federal Reserve maintains these legacy numbers in inactive status, still capable of processing transactions but no longer tied to an independently chartered institution.

The practical result: a business that banked with LegacyTexas before Prosperity's 2019 acquisition might still see the LegacyTexas routing number on their checks while their online banking shows the Prosperity number. Payroll and ACH systems set up years ago may reference routing numbers from banks that haven't existed independently for a decade. When in doubt, Prosperity's customer service team can confirm the active routing number for any account.

The Texas community banking consolidation

Prosperity's acquisition history mirrors what's happened to community banking across Texas and the country. In 1985, Texas had over 1,800 state and nationally chartered banks. By 2024, that number had fallen below 400. Deregulation allowed mergers across county and state lines, the savings and loan crisis wiped out hundreds of Texas institutions, and rising compliance costs made independent operation increasingly difficult for small banks. Prosperity thrived by being the acquirer rather than the acquired — and Zalman's discipline of walking away from overpriced deals has produced returns that significantly outpace the KBW Bank Index over two decades.

When your bank keeps changing its name

Some Texas businesses have banked at the same branch for thirty years but seen four different names on their statements. Routing numbers change, online banking portals change, relationship managers occasionally change. It works, but it's not frictionless. Slash offers a different model: one platform, one routing number, and financial tools that stay consistent regardless of what's happening in the M&A market. Corporate cards, automated expense tracking, and real-time spend visibility — stable infrastructure that doesn't depend on whether your bank is about to be acquired again.