Retainer Agreement — Definition, Context, and Examples
Retainer Agreement is a written contract between an attorney and client specifying the scope of representation, fee structure, advance payment, and terms under which the attorney will provide legal services. This page explains the term in depth, how it is used in law work, and how it relates to adjacent concepts in the professional services operating vocabulary.
What is Retainer Agreement?
A retainer agreement is the foundational contract between a lawyer and a client. It defines what the lawyer will do (scope), how the lawyer will be paid (hourly, flat fee, contingency, hybrid), how much money the client is advancing (the retainer itself), how unused funds are returned, and how and when the engagement ends. In most states, the ABA Model Rules require a written retainer for any engagement above a de minimis amount.
Three common retainer structures exist. A classic retainer is money paid upfront and drawn down as work is billed — the attorney places it in IOLTA and transfers to the operating account only after invoicing. An evergreen retainer requires the client to replenish the balance whenever it drops below a threshold. A fixed-fee retainer covers a defined scope of work regardless of hours.
The retainer agreement is where malpractice claims are won or lost. Ambiguity on scope ("we'll help with your divorce") invites later disputes ("you never said that didn't include the custody modification"). The American Bar Association publishes model retainer language; most experienced firms maintain vertical-specific templates (estate planning, family, criminal, M&A) and run each new engagement through an internal review.
How is Retainer Agreement used in law work?
Example in practice
A bankruptcy attorney uses an evergreen retainer — the client deposits $5,000 and must replenish whenever the IOLTA balance drops below $2,000, ensuring the firm is not financing the representation.
How Retainer Agreement differs from related terms
What is the difference between Retainer Agreement and IOLTA Account?
Retainer Agreement refers to a written contract between an attorney and client specifying the scope of representation, fee structure, advance payment, and terms under which the attorney will provide legal services. IOLTA Account, in contrast, is a pooled trust account where attorneys hold client funds that are too small or too short-term to earn meaningful interest, with the interest remitted to the state bar to fund legal aid. The two show up in the same operational conversations but answer different questions — retainer agreement describes the law artifact itself, while iolta account addresses a related but distinct part of the workflow.
Read the full IOLTA Account definitionWhat is the difference between Retainer Agreement and Engagement Letter?
Retainer Agreement refers to a written contract between an attorney and client specifying the scope of representation, fee structure, advance payment, and terms under which the attorney will provide legal services. Engagement Letter, in contrast, is a written communication from a professional services firm to a client confirming the scope of work, fee arrangement, responsibilities, and terms of the engagement before work begins. The two show up in the same operational conversations but answer different questions — retainer agreement describes the law artifact itself, while engagement letter addresses a related but distinct part of the workflow.
Read the full Engagement Letter definitionWhat is the difference between Retainer Agreement and Billable Hour?
Retainer Agreement refers to a written contract between an attorney and client specifying the scope of representation, fee structure, advance payment, and terms under which the attorney will provide legal services. Billable Hour, in contrast, is a unit of professional time spent directly serving a client and recorded against a specific matter for invoicing, typically tracked in six-minute (tenth-of-an-hour) increments. The two show up in the same operational conversations but answer different questions — retainer agreement describes the law artifact itself, while billable hour addresses a related but distinct part of the workflow.
Read the full Billable Hour definitionWhere does the authoritative reference come from?
The definition and standards governing Retainer Agreement draw primarily from guidance published by American Bar Association. For the most recent rulings, interpretations, and model language, consult the source directly.
Visit American Bar AssociationFrequently asked about Retainer Agreement
What does Retainer Agreement mean in simple terms?
A written contract between an attorney and client specifying the scope of representation, fee structure, advance payment, and terms under which the attorney will provide legal services.
Is Retainer Agreement the same as IOLTA Account?
No. Retainer Agreement and IOLTA Account are related concepts but address different parts of the workflow. Retainer Agreement is a written contract between an attorney and client specifying the scope of representation, fee structure, advance payment, and terms under which the attorney will provide legal services. IOLTA Account is a pooled trust account where attorneys hold client funds that are too small or too short-term to earn meaningful interest, with the interest remitted to the state bar to fund legal aid.
Who typically owns Retainer Agreement in a small firm?
In a small law firm, Retainer Agreement is typically managed by the responsible attorney for the matter, with support from paralegals for preparation and an administrative lead for procedural tracking.
Where is the authoritative standard for Retainer Agreement published?
The most widely cited authority for Retainer Agreement is American Bar Association. Firms should consult the source directly for the most current rules, interpretations, and model language, since guidance is updated regularly.
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