Melio Payments is very similar to Plastiq, which you’ve probably all heard of. It’s a way for you, as a business, to pay a vendor or another business using a debit or credit card (they can also do bank transfers) and by sending either a check or ACH to the vendor.
Debit cards and bank transfers are currently free, while credit card has a 2.5% fee, similar to Plastiq. The ACH transfers to the vendor appear to be faster (within 24 hours), whereas Plastiq may take a few business days. Check speeds are about the same for both, about 7-10 days.