1) look at your watch when you are doing a transaction
2)look regularly at your internet banking. Im not sure mine gives the exact time, but it appears immediately, so if you are looking regularly you can guess approx
3)on the transaction receipt
i just looked on my internet banking - no time (santander)
just says this :CASH WITHDRAWAL AT BARCLAYS BANK PLC ATM xxxxxxxxxx,30.00 GBP , ON 13-02-2018