But in recent years business customers have become more common.
"We really serve as the back office for our business customers."
When calls to business customers are added in, sales came to $385 billion last year, the association says.
Only 10,000 of 500,000 business customers have bought the service.
The chosen few will have to offer support services to business customers.
Two years ago, the bank began to plan a new system of cash management services for business customers.
But consumers and business customers do not use their rights.
The same business customers are also big users of international phone plans.
Big business customers these days do not want to buy communications products by themselves.
No additional information is required to be provided to a business' customers.