I've been doing exactly this for years with Revolut premium (and I'm sure many other "online banks" have the same service). It's like using a password manager, you don't have to worry about how your card details are stored anymore.

It is very neat although I got into strange situations a few times when I needed to prove I was the card owner for a refund or for insurance claims.

Or just reuse them eventually. Wake the number up again for another very specific transaction.

> that I set online to exactly the amount I'm spending

Sounds like it would take longer at checkout though?

Lots of my spending is online. Like everybody else, considering Amazon's success.

Amazon supports direct debit, so you don't even need a card. At least in the SEPA countries.

Ok... sounds like it would take longer at online checkout then.

Unless somebody wrote an app, or the store cooperated like PayPal, or 100 other things.

Lets try to imagine a better future?

Don't you already get this with Verified by Visa and MasterCard SecureCode? You don't need new credit card numbers to do this.

But merchants don't implement it... because it's an extra step and consumers don't like it. The very last thing a merchant wants to do is put an extra step in front of someone just about to buy.

Exactly. That's why, a new number for every transaction. No merchant requirement.

I don't understand how you think you can get a new number for each transaction without any extra step getting in the way? How does your card issuer know you want a new number and how much to set the limit?

Do you go to an app? That's a separate step. Consumers demonstrably don't want extra steps.

Do you integrate it with the merchant and do it automatically? Then it's no safer as there's no authorisation.