This is the largest reason why in-place upgrades to the U.S. financial system are slow. Coordinating the Faster ACH rollout took years, and the community bank lobby was loudly in favor of delaying it, to avoid disadvantaging themselves competitively versus banks with more capability to write software (and otherwise adapt operationally to the challenges same-day ACH posed)."
From the great blog Bits About Money: https://www.bitsaboutmoney.com/archive/community-banking-and...
This is the same in Switzerland. If you request an IBAN transfer, it's never instant. The solution there for fast payments is called TWINT, which works at almost POS terminal (you take a picture of the displayed QR code).
I think BACS is similarly "slow" due to the settlement process.
[0] https://en.m.wikipedia.org/wiki/Faster_Payment_System_(Unite...
But the faster payments ceiling is large enough that buying a house falls under the limit.
I definitely miss it in other places I've worked.
"In 2024, EU adopted Instant Payment Regulation, aiming to accelerate instant payments in Europe. For EU member states operating in euro it partially took affect in January 2025, for non-euro member states it will partially take affect in January 2027. This regulation includes requirements to send and receive transfers within 10 seconds, as well as to implement the Verification of Payee service."
https://real-timepayments.com/Banks-Real-Time-Payments.html
Prior to that, you could get instant transfers but it came with a small fee because they were routed through credit card networks. The credit card networks took a fee but credit card transactions also have different guarantees and reversibility (e.g. costing the bank more in cases of fraud)
Which means nobody can send me money.
FedNow on the backend is supported by fewer banks than Zelle is, which is probably why hardly any banks expose a front-end for it.
The bank had an opportunity to notify me precisely because ACH is not real time. And I had an opportunity to fix it because wire transfers is almost real time (finishes in minutes not days). I appreciate it when companies pull money from my account I get days of notice but if I need to move money quickly I can do it too.
You don't need slow transfers to get an opportunity to satisfy automatic payments. I don't know how it works but in the UK direct debits (an automatic "take money from my account for bills" system) gives the bank a couple of days notice so my banking app warns me if I don't have enough money. Bank transfers are still instant.
I believe this is because Ürs has to load my silver pieces onto the donkey and drive it to the other bank.