Evergreen Retainers: How to Get Paid Before the Work Instead of Chasing It After

Every law firm owner knows the feeling. The work is done, the invoice is out, and now the money belongs to the client until they decide to send it. Some pay in a week. Some pay in ninety days. Some never pay at all, and you find out only after you have already put another thirty hours into their matter.

Most firms try to fix this at the back end, with better reminders, firmer follow-up, and a more disciplined A/R collection process. Those things help. But the most effective fix sits at the front end, before the first hour is billed. It is called an evergreen retainer, and for a lot of small firms it changes the entire cash flow picture.

What an evergreen retainer actually is

A standard retainer is a one-time deposit. The client pays up front, you bill against it, and once it runs out you are back to invoicing and waiting.

An evergreen retainer refills. The client deposits an agreed amount into your trust account. You bill against it as the work happens. When the balance drops below a set floor, the client replenishes it back to the original amount. The retainer never runs dry for as long as the matter is open, so there is always money on deposit covering the work you are doing right now.

The difference sounds small. In practice, it moves the collection risk from you to the calendar. Instead of asking "will they pay this invoice?", the question becomes "did they refill the retainer?", and that question gets asked early, before you are deep in unpaid work.

Why it matters so much for small firms

Think about what unpaid work actually costs you. Every hour you bill and never collect drags down your realization rate, the gap between what you bill and what you keep. A firm with a strong billing rate and weak collections can easily be earning less per hour than a firm with a lower rate and a disciplined retainer policy.

Evergreen retainers attack that gap directly. When there is always money in trust covering current work, write-offs shrink, aging reports get shorter, and the 90-day column stops being a permanent home for your best clients. Cash arrives more predictably, which makes everything else easier: payroll, planning, and building a real cash reserve.

How to size the retainer

The most common mistake is setting the retainer too low. A $2,500 deposit on a matter that runs $8,000 a month is not a retainer. It is a down payment on your next collection problem.

A practical starting point is to size the retainer to roughly one month of expected billing on the matter, then set the replenishment floor at about a third of that amount.

Here is how that looks. Say a litigation matter will likely bill around $6,000 a month. You set the evergreen retainer at $6,000 with a replenishment floor of $2,000. As you bill against it, the balance falls. When it dips below $2,000, the client receives a replenishment request to bring it back to $6,000. At no point are you more than a few weeks of work ahead of the money.

For matters with heavy months (trial prep, closings, discovery deadlines), it is worth building in a mechanism to temporarily raise the retainer ahead of the spike. That conversation is much easier to have in advance than after a $20,000 invoice lands.

Put the terms in writing

An evergreen retainer only works if the client understands it from day one. Your engagement letter should spell out:

• The initial retainer amount

• The replenishment floor and the amount it refills to

• How quickly the client needs to replenish after a request

• What happens if they do not, such as pausing non-urgent work, within the limits of your ethical obligations

• That any unearned balance is refunded when the matter closes

That last point matters more than most firms realize, and we will come back to it.

Remember whose money it is

Retainer funds are client money until they are earned. They belong in your trust account, not your operating account, and every dollar needs to be tracked on that client's individual ledger. Most jurisdictions also expect the client to receive an invoice or notice before earned funds move from trust to operating, so check your state's rule and build it into your billing workflow.

This is where evergreen retainers can quietly create risk. More retainers means more trust activity, which means more individual ledgers to maintain and more transactions to reconcile. If your three-way reconciliation is already shaky, adding a replenishing retainer to every matter will make it shakier. Before you roll this out firm-wide, make sure your trust accounting would hold up to the kind of review covered in our trust account audit checklist.

And when a matter closes, the leftover balance does not belong to you. It needs to go back to the client promptly. Unreturned retainer balances are one of the most common sources of stale money sitting in law firm trust accounts, which is exactly what we unpack in Stale Balances in Your Trust Account: A Year-End Cleanup Guide.

Does this work with flat fees?

Evergreen retainers fit most naturally with hourly work, but the underlying principle applies to any pricing model: get money on deposit before the work, not after. If you are moving toward flat fees or subscriptions, the same logic points to collecting in stages tied to milestones rather than billing in arrears. How flat fees can be handled with respect to trust varies significantly by state, so confirm your jurisdiction's rules before you design the structure.

Start with new matters

You do not need to renegotiate every existing client relationship tomorrow. The cleanest rollout is to require evergreen retainers on all new matters starting on a set date, then transition existing clients at natural points like a new phase of the case or a rate change. Q4 is a good time to set that date, so January starts with the new policy already in place.

Getting the retainer policy right is one of those decisions that pays off every single month afterward. If you want help sizing retainers by practice area, modeling what the change would do to your cash flow, or making sure your trust accounting is ready for the extra activity, that is exactly the kind of work a virtual CFO does. Accounting Girl helps solo and small law firms get paid for the work they do. Let's talk before you send your next engagement letter.