Evergreen Retainers: Auto-Replenishing Client Trust With Card on File
Set up an evergreen retainer that tops itself up: minimum balances, card-on-file authorization language, client notices and what to do when a charge fails.
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On this page 7 sections
- How an Evergreen Retainer Works in Practice
- Setting the Minimum Balance and Replenishment Amount
- Card-on-File Authorization Language for Your Evergreen Retainer Agreement
- Automating Top-Ups to Auto-Replenish the Trust Account
- Notifying Clients Before Each Charge to Prevent Disputes
- What to Do When a Replenishment Payment Fails
- Next Steps for Your Firm
Key takeaways
- An evergreen retainer runs on autopilot only if the agreement spells out the floor, the top-up amount, a per-charge cap and how the client can revoke consent.
- Replenishment deposits are unearned client funds that belong in trust. Processing fees and chargebacks are generally kept out of trust, so confirm your setup with your state bar's guidance.
- A short pre-charge notice and a clear billing descriptor help prevent "I didn't authorize this" disputes.
- Put your failed-charge plan in writing before you need it: retry limits, client outreach and what happens to the work if the balance isn't restored.
An evergreen retainer keeps a minimum balance of client funds in trust and refills it whenever invoices draw it down. Done right, the firm never has to chase a top-up. Many firms still end up sending reminder emails, waiting on checks and pausing work while the trust balance sits near zero. This guide explains how to set a sensible minimum balance, what a client's card-on-file authorization should say, how to automate replenishment from your billing software, and how to handle notices and failed payments without causing disputes or trust accounting problems.
Most of the examples involve law firms, because their trust rules are the strictest. The same structure works for CPAs, consultants and other professionals who bill against a deposit.
This article is general information, not legal or ethics advice. Trust account rules differ by state. Confirm your setup with your state bar's guidance or an ethics advisor.
How an Evergreen Retainer Works in Practice
An evergreen retainer has three parts:
- The deposit. The client pays an initial retainer, which goes into the client trust account as unearned funds.
- The draw. You bill time and costs as usual, typically monthly. Once the client has received the invoice, earned fees move from trust to operating in the way your jurisdiction requires.
- The refill. When the trust balance drops below an agreed floor, the client replenishes it, either back to the original amount or by a fixed sum.
The refill is where firms lose time. Without a card on file, each replenishment depends on the client noticing the request, finding a checkbook or logging in to pay, and doing it before the next invoice. With a stored card and a signed authorization, the refill can run automatically on a schedule the client has already approved.
An evergreen retainer is not the same as a flat fee "earned upon receipt." That arrangement raises a separate question about where the money lands, which we cover in our guide to which account gets a flat-fee card payment. Evergreen replenishments remain unearned client money until billed, so they belong in trust.
Setting the Minimum Balance and Replenishment Amount
The floor should roughly cover what the matter costs in one billing cycle, so you never work ahead of the funds you hold. Set it per matter rather than using a firmwide default.
Factors that should move the number:
- Matter phase. Discovery, trial preparation, a closing or tax filing season burns funds faster than a quiet monitoring period.
- Expected costs. Expert fees, filing fees and deposition transcripts can drain trust quickly.
- Billing frequency. Monthly billing needs a larger floor than biweekly billing.
- Client capacity. A floor the client can't comfortably maintain leads to declines and strained relationships.
Choosing a Replenishment Model
| Model | How It Works | Best For | Watch Out For |
|---|---|---|---|
| Top-up to target | Charge whatever amount restores the original retainer | Litigation and active matters with variable monthly bills | The charge amount changes each month, so clients need clear notice |
| Fixed increment | Charge a set amount each time the balance crosses the floor | Steady, predictable matters | Can fall behind during busy phases |
| Scheduled monthly | Charge a fixed amount on the same date each month | Ongoing advisory or general counsel work | Can overfund trust during slow months |
Illustrative example: A firm sets a $10,000 evergreen retainer with a $4,000 floor on a commercial litigation matter. After the March invoice is paid from trust, the balance is $3,200. Under a top-up-to-target model, the firm charges $6,800 to restore the $10,000 balance. These figures are examples only and do not represent a typical retainer.
Include a per-charge cap, meaning the largest single amount you can charge without fresh client approval. If trial prep requires a larger deposit, ask for it separately instead of letting the automatic charge grow.
Card-on-File Authorization Language for Your Evergreen Retainer Agreement
Card networks have rules for storing cardholder credentials and running charges when the cardholder isn't present. In general, those rules call for clear consent, disclosure of how and when the card will be charged, and notice when terms change. Your processor can tell you exactly what applies to your account. Your engagement letter, or a standalone authorization form, is where you meet those expectations and your ethics obligations together.
What the Authorization Should Cover
- Cardholder name, card brand and last four digits (never the full number on paper)
- The retainer amount, the minimum balance and the replenishment model
- The per-charge cap and the maximum number of charges per month
- How much notice the client gets before each charge, and how it is delivered
- That replenishments are deposited into trust and applied only to billed fees and costs
- How unearned funds are refunded when the matter ends
- How the cardholder can revoke or update the authorization, and whom to contact
- How the charge will appear on the card statement
- Signature and date
If someone other than the client pays, such as a parent, employer or business partner, you have a third-party payor arrangement. The authorization should come from the cardholder. The engagement should also address the client's informed consent, confidentiality and the fact that the payor does not direct the representation. Talk to your ethics advisor before accepting these arrangements.
Sample Clause (Illustrative Only)
"I authorize [Firm] to charge the card ending in [XXXX] to replenish my trust balance to $[amount] whenever it falls below $[floor], up to $[cap] per charge and no more than [number] times per calendar month. I will receive written notice at least [number] business days before each charge. I may revoke this authorization in writing at any time, without affecting amounts already billed."
Have an attorney adapt this language for your jurisdiction. For broader wording on fee terms, see our guide to engagement letter payment terms that prevent fee disputes.
Automating Top-Ups to Auto-Replenish the Trust Account
Automatic trust replenishment depends on your billing system and your payment setup working together. A typical automated flow looks like this:
- An invoice is issued and, once permitted, earned fees are applied from trust.
- The system compares the new trust balance with the matter's floor.
- If the balance is below the floor, the system calculates the replenishment amount and checks it against the cap.
- A pre-charge notice goes to the client.
- After the notice window closes, the stored card is charged and the funds are deposited to the trust account.
- The client receives a receipt, and the deposit is recorded against the matter for reconciliation.
Tokenization is what makes a stored card workable. Tokenization replaces the card number with a token that software can reuse, so no one at the firm stores or sees full card data. Ask your gateway and billing software provider how they handle stored credentials. Never keep card numbers in matter notes, intake forms, email or spreadsheets, because doing so creates PCI DSS exposure and privacy risk.
When you compare tools, ask whether the software handles matter-level floors, caps and notices natively or only offers generic recurring billing. Our guide to choosing recurring billing software walks through those questions. Practice-management payment add-ons also differ in how they handle trust, which we cover in LawPay vs. Clio Payments vs. Headnote.
MannyPay offers payment gateways, including Authorize.net and NMI, integrations with tools such as QuickBooks and Salesforce, and virtual terminals for one-off keyed charges when a client wants to pay a larger deposit by phone.
Keep Processing Fees and Chargebacks Away From Trust
Card processing fees are generally treated as a firm expense, and trust rules in many states restrict deducting them from client funds. One common setup deposits the full replenishment amount into trust and debits fees and any chargebacks from the operating account. Confirm this configuration with your processor in writing before the first charge, and check your state bar's guidance on the approach.
Stored-card charges are card-not-present transactions, which generally cost more to process than in-person payments. Our explainer on card-present vs. card-not-present fees and fraud rules explains why. Whether a surcharge or cash discount program can apply to trust deposits is a separate legal and ethics question, so get advice before adding one.
Notifying Clients Before Each Charge to Prevent Disputes
Many retainer chargebacks aren't fraud. They often happen when a client sees an unexpected charge, doesn't recognize the descriptor or disagrees with the invoice behind it. A short notice can prevent many of these disputes.
A good pre-charge notice includes:
- The matter name and the invoice that triggered the replenishment
- The current trust balance, the floor and the amount to be charged
- The charge date and the card's last four digits
- How the charge will appear on the statement
- A direct contact for questions before the charge date
After the charge, send a receipt showing the new trust balance. Make sure your billing descriptor matches the firm name clients know, because an abbreviation they can't recognize invites disputes.
If a client questions an invoice during the notice window, hold the charge until the question is resolved. A dispute through the client's bank is slower and more costly for everyone. If one does come in, it helps to understand how the chargeback lifecycle works. Your signed authorization, notices and receipts form the core of your chargeback rebuttal evidence.
What to Do When a Replenishment Payment Fails
Cards expire, get reissued after fraud or hit their limits. Decide in advance what happens next and put it in the engagement letter.
| Decline Type | Common Causes | Response |
|---|---|---|
| Soft decline | Insufficient available credit, temporary issuer hold | Retry once or twice over a few days, then contact the client |
| Hard decline | Closed, lost, stolen or expired card | Don't retry. Request updated card details and a new authorization if the card changed |
| Suspected fraud flag | Issuer blocked an unusual amount | Ask the client to call the issuer, then retry |
A practical failed-payment playbook:
- Notify the client the same day with the amount, the reason category and a secure way to update the card.
- Limit retries. Repeatedly retrying a hard decline can draw scrutiny from issuers and processors.
- Ask about account updater services. Some processors can refresh reissued card details automatically, which reduces declines from expired cards.
- Offer an alternative, such as ACH or a one-time payment, for clients who prefer not to put large deposits on a card.
- Follow your engagement letter on what happens to the work if the trust balance isn't restored. Any decision to slow or end representation involves professional obligations, so involve your ethics advisor.
If the matter ends with funds still in trust, return the unearned money promptly. Our guide to refunding an unearned retainer compares the options.
Next Steps for Your Firm
Start with one active matter:
- Set its floor, cap and notice window.
- Have the client sign an authorization reviewed by counsel.
- Confirm with your processor that fees and chargebacks debit operating, not trust.
- Run one full cycle, from invoice to notice to charge to receipt to reconciliation, before rolling the process out firmwide.
If you're setting up card-on-file billing for a law, accounting or consulting practice, MannyPay works with professional services firms on gateways, virtual terminals and integrations. You can request a free quote, and a MannyPay specialist will respond within one business day.
This article is for general educational purposes and is not legal, tax or financial advice. Card network rules and state laws change; confirm current requirements for your business.
