Blockchain, a record-keeping technology that powers Bitcoin—the first digital currency—has irrevocably gone mainstream. Until most recently, Bitcoin was infamously associated with drug dealers, pornography, and the illicit weapons trade.

But now big banks are willing to implement blockchain. According to new market report financial and technology markets will invest $1 billion in blockchain this year.It turned out that blockchain is just a universal banking protocol and everything blockchain needs is already here, from mobile phones to embedded sensors, from raw computing power to machine algorithms.

The enthusiasm of big banks is understandable. The regulatory pressure to record everything from stock trades to money transfer has caused compliance costs to escalate astronomically in recent years.

So what will happen in the future after most banks have adopted blockchain? According to standard economic theory, a low-cost competitor enjoys cost advantage only when high-cost competitors still remain in the market. When everyone is using blockchain, the resultant saving will stop flowing in as corporate profit. Market competition will force all banks to pass on the hard-won saving back to consumers. Banking fees are set to plunge.