Law Firm Payment Processing, Done Compliantly
Quick answer: Law firms can accept credit cards and ACH, but processing fees can never be deducted from a client trust (IOLTA) account. The compliant setup uses a payment processor that deposits client funds into trust at 100% and pulls all fees from your operating account separately. Pair that with interchange-plus pricing, Level 2/3 data for lower rates on corporate cards, and ACH for large invoices to keep costs down.
Most payment processors are built for retail. They net out fees before depositing your money, which is fine for a coffee shop but a serious ethics problem for a law firm. If a processing fee is pulled from your IOLTA trust account, you have commingled funds and potentially misappropriated client money, even if the amount is a few cents.
The single most important rule of legal payments: the client's full payment must land in trust, and every fee must come out of operating, never trust.
Why Generic Processors Put Your Bar License at Risk
Square, Stripe, and PayPal deposit your sales minus their fee. For a $2,500 retainer at 2.9% + $0.30, you would receive about $2,427 and the missing $73 came directly out of the deposit. If that deposit was supposed to be unearned client money sitting in trust, you are now $73 short in IOLTA, which is a reportable trust accounting violation in most states.
A second problem is timing. Aggregators frequently hold or freeze funds when they see large, irregular transactions, which is exactly what a litigation retainer looks like. A frozen retainer can stall a representation and damage the client relationship.
The Compliant Architecture for Legal Payments
A legal-specific merchant account is configured so that:
- Client payments deposit at 100% into your IOLTA trust account.
- All discount fees, monthly fees, and per-item fees are debited from your operating account on a separate schedule.
- Earned fees (paid invoices for work already completed) deposit into operating as normal.
This separation is the entire game. It lets you accept cards for unearned retainers without ever commingling funds.
| Payment type | Where it should deposit | Where fees come from |
|---|---|---|
| Unearned retainer / advance | IOLTA trust (100%) | Operating account |
| Earned fee (completed work) | Operating account | Operating account |
| Flat fee collected upfront | IOLTA until earned | Operating account |
| Reimbursable costs advanced by client | IOLTA trust | Operating account |
Surcharging and the "Pass the Fee to the Client" Question
Many firms want to pass processing costs to clients. You can, but there are two hard limits. First, card network rules cap credit card surcharges and require signage and disclosure. Second, you generally cannot surcharge a payment into a trust account, because adding a surcharge to an unearned deposit creates the same commingling issue in reverse. Surcharging is cleanest on earned, operating-account invoices.
For trust deposits, the compliant alternative is to absorb the fee in operating and treat it as a cost of doing business, or to steer larger retainers to ACH, where the flat per-transaction fee is a few cents rather than a percentage. See our breakdown of cash discount vs surcharge vs convenience fee for the rules that apply.
Lower Your Rates with Level 2 and Level 3 Data
Law firms bill a lot of business clients, and business, corporate, and government cards carry higher interchange unless you submit Level 2 and Level 3 data (tax amount, invoice number, line-item detail). Submitting this data can drop interchange on qualifying commercial cards by 0.50% to 1.00%.
For a firm running $80,000 a month in commercial card payments, Level 3 optimization alone can save $400 to $800 every month. Flat-rate processors cannot do this, which is another reason interchange-plus is the right model for legal.
Getting Paid Faster: Retainers, Invoices, and Trust
The practical workflow most firms want:
1. **Send a payment link or text-to-pay request for the retainer, routed to trust. 2. Store the card on file (tokenized, PCI compliant) so you can replenish a depleted retainer with client authorization. 3. Invoice earned fees from operating, where you can surcharge if you choose. 4. Use ACH for high-dollar matters** to avoid percentage-based fees on $10,000+ payments.
Card on file is especially powerful for evergreen retainers. When trust drops below the agreed floor, you charge the authorized card to top it back up, with the funds again landing in trust, not operating.
Software Integrations
If your firm uses Clio, MyCase, PracticePanther, or QuickBooks, your processing should reconcile cleanly with trust ledgers. The key questions to ask any provider:
- Does the deposit hit IOLTA at 100% with fees pulled separately?
- Can fees be debited from a designated operating account on a fixed monthly date?
- Is Level 2/3 data supported for commercial cards?
- Are there long-term contracts or early termination fees? (There should not be.)
What It Costs
Legal payment processing should use transparent interchange-plus pricing, not flat-rate or tiered. Expect an effective rate in the 2.2% to 2.7% range on consumer cards, lower with Level 3 on commercial cards, and a few cents per ACH transaction. Avoid any provider that cannot clearly explain how fees stay out of your trust account, and read how to read your merchant statement so you can verify it yourself.
Contact Unison to set up IOLTA-compliant law firm payment processing, or compare pricing.