Start with the actual numbers rather than the headline rate. Card processing is typically quoted as a percentage plus a fixed amount per transaction, and the fixed component matters enormously at small ticket sizes. A charge of thirty cents on a ten dollar sale is three percent on its own before the percentage applies. Businesses selling low value items frequently discover their effective rate is nearly double the advertised one, and the fix is minimum order values or bundling rather than a different processor.
Bank transfer, sometimes offered as direct debit or an equivalent, costs a small flat fee or nothing at all depending on the arrangement. It is slower to settle, it requires the customer to take an action rather than entering a card, and it is entirely appropriate for recurring work with established clients. For a business invoicing the same customers monthly, moving those payments off cards is a straightforward margin improvement that requires one conversation each.
Keep cards available for everything else. A new customer, a one off purchase, or anything where friction costs you the sale should be as easy as possible, and asking somebody to arrange a transfer at the moment they decided to buy loses a proportion of them. The saving on a first transaction is never worth the transaction.
Watch the charges that do not appear in the headline rate. International cards, manually entered transactions where the card is not present, chargebacks, and monthly account fees all sit outside the quoted percentage. The number worth tracking is total processing cost divided by revenue, calculated monthly, which is frequently higher than the advertised rate by a meaningful margin and is the only figure that lets you compare providers honestly.
Consider settlement timing alongside cost, because for a business without reserves it matters more than the fee. Standard settlement is typically a couple of business days and can be longer for new accounts, and some processors hold a reserve against chargebacks in higher risk categories. A slightly cheaper processor that settles a week later can be the more expensive choice in practice.
Be careful with the instinct to pass fees to customers. Surcharging is permitted in many circumstances and regulated in specifics, it must be disclosed, and it is prohibited outright on some card types and in some states. It also reads badly at the point of purchase, which is the worst possible moment to introduce friction. For most small businesses, building the cost into the price is simpler and converts better.
Cash has no processing cost and real handling costs that people forget: counting, reconciliation, trips to the bank, and the risk of holding it. For most businesses it is worth accepting and not worth encouraging.
The practical arrangement for a first year business is one mainstream processor for cards, connected to your accounting software so transactions reconcile automatically, plus bank transfer offered on invoices for recurring or larger amounts. That covers nearly every situation, keeps the administration in one place, and captures most of the available saving without a project.
Review the arrangement annually, because processing rates are more negotiable than most small businesses assume once there is a volume history to point at. A year of consistent processing and a low dispute rate is a reasonable basis for asking, and providers will frequently improve terms for an existing customer rather than lose one. The request costs a phone call and is almost never made.