The Treasury Department has temporarily OK’d relief transactions. But most major money transfer companies won’t remit aid from the U.S. to Syria.

In a typical year, they send more than $500 million to family and friends. Now, it’s not easy.

The remittances business is getting crowded, and customers have more options.

A network that would let consumers and businesses instantly move money around has already been adopted by several big banks. But for it to truly catch on, financial products will have to incorporate the system into their own services.