Helcim fees for retailers, next to Payzium's published rate.

Helcim column: its published in-person, $0 to $50k per month band at Interchange + 0.40% + $0.08 [1]; in-person, $100k to $500k per month band at Interchange + 0.25% + $0.07 [9]; online, $0 to $50k per month band at Interchange + 0.50% + $0.25 [3]; online, $100k to $500k per month band at Interchange + 0.35% + $0.20 [12]. Payzium column: interchange and network assessments at cost, the published margin at the tier for that volume, the per-transaction fee and the monthly account fee. A positive difference means Helcim costs more.

Helcim's band is chosen by each row's monthly volume. Its margin and per-transaction fee are applied to every card transaction, credit and debit, which is how its published schedule reads; Helcim publishes no credit-only carve-out. Interchange passes through at the same rates the Payzium column uses.

Average ticket sets the competitor's per-transaction count. Payzium's per-transaction line is counted at the $50 sitewide ticket assumption the calculator uses.

The Payzium column is the calculator's engine, so the calculator's disclosure applies here as written:

Calculator output is an estimate. Final pricing depends on your actual card mix, current network rates effective on the date of your transactions, and any optional add-ons. The model assumes an average transaction value of $50. Visa and Mastercard revise their US interchange schedules twice a year; this calculator reflects schedules effective April 2026.

Retail sits in the middle of the card-cost range. Tickets are larger than a restaurant's, most transactions are still card-present, and the card mix leans toward consumer credit, with rewards cards common in apparel, electronics and specialty stores. That mix is exactly where a flat rate and a published margin drift apart, because rewards interchange is higher than standard interchange and a flat rate prices every card as if it were the expensive kind.

Returns and exchanges deserve a line of their own. On many plans a returned sale does not give back the processing fee, and on some plans the return itself carries a fee, so a store with a generous return policy pays for cards twice on the same sale. Chargebacks follow the same logic; a store that sells online as well as in person will see a higher dispute rate on the online share, and the fee per dispute varies widely between processors.

Seasonality is the third factor. A retailer that does a large share of the year in the last quarter is often placed in a pricing tier by its average month, and then pays the tier's per-transaction fee on the busy months at a rate that was set for the quiet ones. Interchange-plus does not use tiers in that sense; the margin is the margin regardless of the month.

The table above uses a typical retail ticket and a card-present share that assumes most sales happen at the counter with some online orders. A store that sells mainly online should read the online comparison instead, since keyed and e-commerce interchange rates are higher and the difference between plans is larger there.