[unscaled]

I wouldn't call the wire transfers exactly instant (perhaps it depends on the bank?), but they should be at least same-day in most cases if you're doing an online wire transfer.

The main problem is that most services that accept a wire transfer might take a while to verify your bank transfer and will often not verify bank transfers outside business hours, so they're not quite as perfect as I would want them to be. If the bank systems could only have been upgraded to support including a reference number, or better yet provide a system for automatic verification by the submitter (such as a request link + verification link, tokens, QR code)... But I'm dreaming about change to some very old systems.

[kalleboo]

I've sent wire transfers between about, 5 or so different banks? Including like "from Akita bank to Kagoshima bank" not exactly big banks. And it's always done within like 15 seconds, since the Zengin upgrade a bunch of years back.

That said automaticly registered wire transfers aren't really used much lately in my experience. Mostly for stuff like salary, rent and big purchases like a car. Anything else that's automatic people just use cards for now. Precisely due to that lack of messaging/attribution.

For small daily person-to-person transfers, everyone I know uses PayPay since you just exchange phone numbers instead of more personal details. This is similar to back in Sweden where everyone uses Swish instead of regular wire transfers.

[sirn]

Zengin (the interchange network) actually supports 24x7 real-time transfers and EDI data (ZEDI based on ISO 20022, which is built so that you can include invoice number, reference number, etc.) since the end of 2018 or so with the introduction of More Time System and 7th Gen Zengin System. Sadly, it's the bank and bureaucracy that's holding back here (e.g., some smaller banks still refuse to connect to More Time outside their business hours).