Standard ACH payments take between 1-3 business days to settle. ACH payments below $25,000 sent before 2:00PM ET will settle same-day. Settlement times can vary based on the policies of the recipient bank. However, there are two types of ACH transactions a "push" and a "pull." Typically an ACH pull can take 2-3 business days, a push can be 1-3 business days.
The difference between an ACH push versus pull payment is who is initiating the transfer. A push occurs when the sender initiates the transfer by sending money that is already verified. With a pull, the recipient initiates the transfer by requesting money from the sending account (this requires additional verification from the sending bank).