How would payments between Texas and the U.S. work?

The same way payments already move between any two countries with deep trade ties, which is to say constantly, reliably, and mostly invisibly. The global system for moving money across borders already exists, Texas and the United States already use it, and keeping the dollar in circulation makes Texas-to-U.S. payments simpler than almost any pair of countries on earth.

Cross-border payments are a solved, everyday system

Money crosses borders every second of every day. The world runs on a mature system for it: banks send standardized payment instructions to one another over the global messaging network most people know as SWIFT, and they settle through correspondent banking relationships, the partner accounts banks hold with one another specifically to clear international transactions. This is not new infrastructure anyone would have to build. It is the plumbing that already moves trillions between countries, and Texas banks already plug into it.

Keeping the dollar removes the hardest part

The friction in international payments usually comes from currency conversion between two different monies. An independent Texas can sidestep most of that by keeping the dollar in circulation through the transition. When both Texas and the United States are transacting in dollars, a payment between them does not need to be converted from one currency to another. That makes Texas-to-U.S. payments closer to a domestic transfer than a typical international one, simpler than payments between, say, the United States and Canada, which run smoothly every day regardless.

Texas and the U.S. already move enormous sums across this line

This is not theoretical volume. Texas and its neighbors already conduct hundreds of billions of dollars in trade, with money flowing across the border in both directions constantly. The banks, the networks, and the settlement relationships that carry that flow are in place right now. Independence converts an internal flow into a cross-border one in legal category, but the rails it runs on do not change. The same correspondent relationships and networks keep clearing the payments.

The transition is built to keep the rails open

After a vote, banking and payments continuity is a first-order priority in the negotiated transition, for both sides. Both governments have an overwhelming interest in keeping commerce flowing across the Texas-U.S. line, which means keeping payments seamless. Arrangements to ensure banks and financial institutions keep operating across the border without disruption to accounts or services are exactly the kind of detail the transition is designed to settle.

Cards and consumer payments just keep working

For an ordinary Texan, cross-border payments are mostly invisible already. Your card works when you buy something from a U.S. company online today, and it keeps working after independence, on the same global networks. Sending money to family or a business across the line uses the same bank transfers and services that already cross borders worldwide. The consumer experience does not change in any way most people would notice.

The bottom line

Payments between Texas and the United States work the way cross-border payments already work everywhere, over global networks and correspondent banking, and keeping the dollar makes them simpler than most. The system exists, both sides already use it, and the transition is built to keep it running without a hitch.