Largely depends on which banks are talking between each other. For many banks and large transfers you need to wait an hour or so for it to go through.

You notice it most when buying a house and you sit awkwardly in a room with the seller waiting for the money to be transferred so you can leave with the keys.

What awful bank have you got where it takes 1h to do a Faster Payment?

Like I said it depends on the banks.

Santander to HSBC is a pretty slow one for some reason.

I’ve had some slow transfers from HSBC to Barclays too.

In Sweden it took about an hour for Handelsbanken to Nordea, so I’m comfortable saying that there’s some kind of threshold that’s universally accepted for large bank transfers during working hours.