[Nextgrid]

Some modern banks (Monzo, Starling, etc) give the account holder (read-only) access to their API.

If you can't, you can try use one of the open banking providers such as TrueLayer, Plaid, Nordigen (seems to be acquired by GoCardless: https://gocardless.com/bank-account-data/), etc. Most have a free/dev tier that nevertheless allows connections to real accounts and might be enough for personal use.

Finally, screen-scraping is potentially an option. One of the few benefits of shifting everything to SPAs is that you generally have clean JSON APIs under the hood that are easier to interface with than "conventional" screen-scraping involving parsing HTML.