Law firm and professional services credit card processing

Key takeaways

1. What is standard in law & professional services

Common pricing models: Flat rate, interchange-plus with trust/operating split.

What drives cost

• Invoice and online payments
• Large tickets
• Trust vs operating routing
• ACH availability

2. What the rules say

Plain-English summary as of November 1, 2026. Rules change; verify current rules with the card networks, your state and your own advisor. Not legal or tax advice.

For law & professional services

• Client funds held in trust (IOLTA) must be safeguarded and kept separate. State bars generally require that processing fees and chargebacks not reduce trust balances; fees are usually drawn from the firm's operating account. Follow your state bar's current rules. Sources: ABA Model Rule 1.15 (safekeeping property); American Bar Association: IOLTA.
• Some state bar ethics opinions address whether lawyers may pass card fees to clients and how. Check your state bar before adding any fee. Source: American Bar Association: IOLTA.

Surcharges, cash discounts and debit (all industries)

• Surcharges under card-network rules apply to credit cards only, never to debit or prepaid cards, even when a debit card is run as credit. Sources: Visa: merchant surcharging and fees; Mastercard: merchant surcharge rules.
• Network rules generally require advance notice to the network or your provider, disclosure at the store entrance (or first page online) and at checkout, and the surcharge shown as a separate receipt line. Network caps sit around 3% and may not exceed your cost of acceptance; confirm the current cap in the network rules. Sources: Visa Core Rules (public); Mastercard Rules.
• Some states ban or cap surcharges, and some state laws have been challenged in court, so the current rule in your state may differ from what you've read. Check your state attorney general's office and get advice before you start. Source: Find your state attorney general (NAAG).
• A cash discount (a lower price for cash or other non-card payment) is treated differently from a surcharge. Federal law lets merchants offer discounts for paying by cash, check or debit, and networks allow properly disclosed discount and dual-pricing programs. Signage and receipts still must be accurate. Source: 15 U.S.C. § 1693o-2 (discounts for cash, check and debit).
• Debit interchange for large issuing banks is capped under the Federal Reserve's Regulation II, which is one reason debit usually costs less than credit. Source: Federal Reserve: Regulation II (debit interchange).
• Card-interchange litigation: a proposed settlement between merchants and the major card networks has only preliminary court approval. Nothing changes for merchants until final approval is granted and the networks implement new rules. Source: Consumer Financial Protection Bureau.

3. Net profit impact calculator

4. Common questions