Retainer calculator

Estimates only. Appropriate retainer amounts depend heavily on case type, jurisdiction, and firm practice. This calculator provides a general starting estimate only, not a formal fee recommendation. See our full disclaimer.

Retainer estimator

Hourly billing rate ($/hr)

Matter type

Estimated hours for the first phase of work A rough estimate of hours to reach the next major milestone (e.g. initial filings, first mediation, discovery phase).

Client relationship

Estimated retainer amount

Need help setting up your retainer and billing process?

A practice consultant can help you structure evergreen retainers, trust accounting, and client billing workflows correctly from the start.

How should a retainer amount actually be calculated?

A reasonable starting point is your hourly rate multiplied by a realistic estimate of hours needed to reach the next meaningful milestone in the matter, not the entire case from start to finish. Adding a buffer, commonly 20 to 30% above that baseline estimate, accounts for the reality that most matters take longer than initially projected, and running out of retainer mid-task creates friction for both firm and client.

Case complexity matters significantly here - a straightforward uncontested matter needs a much smaller retainer than active litigation with depositions and motion practice ahead. Once you've estimated an appropriate amount, our retainer agreement builder and engagement letter builder help formalize the terms in writing, and tracking hours against the retainer as work progresses with our legal time tracker keeps both sides aligned on remaining balance.

What's the difference between an evergreen retainer and a flat retainer?

An evergreen retainer requires the client to replenish the account back to an agreed floor amount as it's drawn down, keeping a consistent buffer available throughout the matter. A flat, one-time retainer is drawn down until exhausted, at which point the client either pays a new retainer or moves to direct hourly billing. Evergreen structures reduce the risk of an unfunded account partway through active work, which is why many firms prefer them for longer matters.

Should the retainer size differ for a new versus returning client?

Many firms do adjust based on relationship history - a new client with no track record sometimes warrants a somewhat larger initial retainer as a form of commitment and cash flow protection, while a long-standing or referred client with established trust might reasonably start with a smaller amount. This isn't a universal rule, but it's a common practical consideration.

What happens to unused retainer funds at the end of a matter?

Unused retainer funds held in a client trust account generally must be returned to the client once the matter concludes and all fees are settled - this isn't optional and is a core trust accounting obligation under most state bar rules. Clearly explaining this upfront helps clients understand the retainer is their money held for the matter, not a nonrefundable fee paid to the firm.

Frequently asked questions about retainers

No, though the terms sometimes get used loosely. A true retainer is typically an advance deposit against future hourly billing, held in trust and drawn down as work is performed. A flat fee is a fixed total price for a defined scope of work regardless of actual hours spent, and depending on jurisdiction may or may not need to be held in trust the same way.

Generally, true retainers held against future hourly billing must remain refundable for any unearned, unused portion, since ethics rules in most states treat client funds as belonging to the client until actually earned. Some states do recognize a distinct "true retainer" or "engagement retainer" concept that can be non-refundable if specifically structured that way, but this varies significantly and should be confirmed against your specific state's rules.

This should be addressed explicitly in the fee agreement signed at the outset - typically either the client replenishes the retainer to continue evergreen-style, or the firm switches to direct invoicing for hours beyond the retainer amount. Clear communication before the retainer is exhausted, rather than after, keeps this transition smooth for both sides.

No. Contingency fee matters, like many personal injury cases, typically don't require an upfront retainer since the attorney is paid from any eventual recovery instead. Flat fee arrangements for defined, limited scope work also sometimes skip a traditional retainer structure. Retainers are most common for hourly-billed matters with an uncertain total time commitment.

Regular reporting, commonly monthly alongside a detailed invoice, is standard practice and often required by trust accounting rules regardless of preference. Showing the beginning balance, amounts billed against it, and the remaining balance on each invoice keeps the client informed and reduces the likelihood of an unwelcome surprise when the retainer needs replenishing.