Professional Liability (E&O) Insurance for Washington and Idaho Businesses

Professional liability insurance, also called errors and omissions (E&O), covers claims that your work, advice, or services caused a client a financial loss, including the cost of defending those claims. General liability does not cover these claims. Most E&O is written claims-made, so it covers claims reported while the policy is active. Few Washington professions are required by law to carry it, but client contracts often require it.

By Trella Commercial · Updated October 23, 2026

The short version

What it covers: claims that a mistake, oversight, missed deadline, or bad advice in your professional work cost a client money, plus legal defense, even when the claim has no merit.
Why general liability is not enough: general liability covers bodily injury and property damage. Washington's state contracting guidance says plainly that general liability policies exclude professional liability.
How it works: most E&O is claims-made. The policy in force when the claim is reported responds, for work done after the retroactive date. When a policy ends, a tail (extended reporting period) keeps the window open.
Who must carry it: in Washington, almost no one by licensing law; contracts and clients drive it. In Idaho, lawyers who represent private clients and all active real estate licensees are required to carry it.
What contracts ask for: state contracts we reviewed require $1 million to $2 million per claim, and keeping coverage in place for two to five years after the work.

What professional liability covers and does not cover

Usually covered	Usually not covered
Negligent errors, omissions, and mistakes in your professional services	Bodily injury and property damage (that is general liability)
Failure to deliver services as promised, or missed deadlines	Data breaches and ransomware (that is cyber)
Bad advice or recommendations a client relied on	Intentional wrongdoing and fraud
Defense costs and settlements or judgments	Claims from your employees (that is EPLI)
Some policies: copyright or defamation in work you create	Fines, penalties, and contract guarantees beyond your normal duty of care

Who needs professional liability insurance

Business	Typical claim
Consultants and advisors	A client says your recommendation caused a failed project or lost revenue
Technology, software, and IT companies	Software fails or an implementation goes wrong and the client loses money
Marketing and creative agencies	A campaign misses its promised results, or content infringes someone's rights
Architects, engineers, and designers	A design error leads to costly rework
Accountants and bookkeepers	A tax or bookkeeping mistake costs the client penalties
Real estate and property professionals	A missed disclosure or contract error
Staffing and recruiting firms	A placement or screening failure
Anyone whose client contract requires it	The contract makes the coverage a condition of the work

More by profession: consultants, accountants and bookkeepers, law firms, IT consultants and MSPs, and real estate agents.

Claims-made coverage, retroactive dates, and tail

Term	What it means
Claims-made	The policy in force when the claim is first made and reported responds, not the policy in force when the work was done
Retroactive date	Work done before this date is not covered. Keep the same retroactive date when you renew or switch insurers
Extended reporting period (tail)	Extra time to report claims after a policy ends, for work done before it ended and after the retroactive date
Prior acts coverage	Coverage for work done before the policy started, back to the retroactive date
Defense inside limits	Defense costs reduce the limit available to pay a settlement or judgment

Timing matters in Washington. In Safeco Title Insurance v. Gannon (1989), a Washington court enforced a claims-made policy's reporting deadline and denied coverage, without requiring the insurer to show the late notice harmed it. Report potential claims as soon as you learn of them.

How long claims can surface after the work

State	Deadline to sue for professional negligence	Source
Washington	Three years, starting when the client discovers or should have discovered the problem; for lawyers, paused while the lawyer keeps representing the client on the same matter	RCW 4.16.080; Peters v. Simmons (1976); Janicki Logging v. Schwabe (2001)
Idaho	For professionals licensed in Idaho: two years from the act or omission, once some objectively ascertainable damage exists; not extended by an ongoing professional relationship (narrow exception for fraudulent concealment)	Idaho Code 5-219(4); Chicoine v. Bignall (1992)
Design and construction	Washington: claims must arise within six years after substantial completion or the end of services (RCW 4.16.310). Idaho: tort claims start their clock no later than six years after final completion (Idaho Code 5-241)	RCW 4.16.310; Idaho Code 5-241

Washington's discovery rule means a claim can arrive years after the work, which is why the length of your tail matters when you retire, sell, or close a business.

Washington and Idaho requirements

Profession	Washington	Idaho
Lawyers	Not required, but lawyers without at least $100,000 per occurrence and $300,000 aggregate must tell clients in writing and get written consent (RPC 1.4(c)); each lawyer's insurance status is made public (APR 26)	Required for lawyers representing private clients: at least $100,000 per occurrence and $300,000 aggregate (Bar Commission Rule 302)
Real estate licensees	Not required by licensing law	Required: at least $100,000 / $300,000 for individuals and $500,000 / $1,000,000 for firms, not counting defense costs, with at least a 90-day extended reporting period (Idaho Code 54-2013; IDAPA 24.37.01.100)
Escrow agents	E&O of at least $50,000 aggregate (or a $50,000 cash or securities deposit), plus a $1,000,000 fidelity bond (RCW 18.44.201)	Not reviewed in this guide
Structural pest inspectors	Financial responsibility required; a $25,000 E&O policy is one option (RCW 15.58.465)	Not reviewed in this guide
Architects, engineers, CPAs, home inspectors, appraisers, insurance producers	Not required by licensing law	Architects, engineers, and CPAs not required by licensing law

Notaries in both states, and Washington mortgage brokers, post surety bonds, not E&O. A bond protects the public; if the surety pays a claim, the bonded professional usually has to repay it.

What contracts ask for

Contract	Professional liability requirement
Washington statewide IT project management contract (14822)	Technology E&O of $2,000,000 per occurrence and $4,000,000 aggregate when the agency requires it; claims-made coverage kept for three years after the contract
One Washington DES design-build project (2023-166)	Design E&O of $2,000,000 per claim and $4,000,000 aggregate, renewed for five years after completion
Idaho Department of Education solicitation template	$1,000,000 per occurrence and $2,000,000 aggregate, with a 24-month tail or a qualifying retroactive date

Private contracts vary just as widely. Paste yours into our contract insurance checker to see the limits and terms it requires.

E&O and AI

If you use AI tools in client work, confirm your E&O covers services delivered with AI and has no AI exclusion. See when your AI gives a wrong answer and AI exclusions in business insurance.

Common questions

What is professional liability insurance?

Insurance that covers claims that your professional work, advice, or services caused a client a financial loss, including legal defense. It is also called errors and omissions (E&O) insurance, and malpractice insurance in some professions.

Is E&O the same as professional liability?

Yes. Errors and omissions, professional liability, and malpractice insurance are names for the same kind of coverage. Technology E&O is the version written for software and IT companies, often combined with cyber.

Does general liability cover professional mistakes?

No. General liability covers bodily injury, property damage, and personal and advertising injury. Washington's state contracting guidance notes that general liability policies exclude professional liability.

Is professional liability insurance required in Washington?

For most professions, not by law. Washington does not require architects, engineers, CPAs, home inspectors, or real estate brokers to carry it under their licensing laws. Escrow agents must carry E&O or post an equivalent deposit, and lawyers without coverage must disclose that to clients. Client and government contracts often require it.

What does claims-made mean?

A claims-made policy covers claims first made and reported while the policy is active, for work done after its retroactive date. If you cancel without buying a tail or replacing the policy with one that keeps your retroactive date, claims reported later are not covered, even for work done while you were insured.

Sources

This guide is general information, not legal advice. Coverage depends on the policies actually issued. Laws were checked against primary sources in October 2026.

Every guide in this series

Professional Liability Insurance for Consultants
Professional liability and errors and omissions (E&O) insurance for consultants and advisors in Washington and Idaho: what it covers, what client and government contracts require, how much to carry, claims-made and tail coverage, AI-assisted work, and what else consultants usually need.
How Much Does Professional Liability (E&O) Insurance Cost?
What drives the cost of professional liability and errors and omissions (E&O) insurance for Washington and Idaho businesses: your profession and services, revenue, limits and deductible, claims history, contract requirements, retroactive date, defense terms, and how to lower the premium without losing coverage.
Claims-Made vs Occurrence Insurance: What Is the Difference?
The difference between claims-made and occurrence insurance policies, with examples: retroactive dates, prior acts, extended reporting periods (tail), switching insurers, retiring or closing a business, how Washington courts treat late notice under claims-made policies, and which business policies use which form.
Tail Coverage (Extended Reporting Period) for Professional Liability
What tail coverage, or an extended reporting period, is and when you need it: closing, selling, or retiring from a business, switching insurers, and contracts that require it. How long a tail to buy in Washington and Idaho, and what a tail does and does not cover.
How Much Professional Liability (E&O) Insurance Do I Need?
How to choose professional liability (E&O) limits: per claim and aggregate limits, what Washington and Idaho contracts and rules require, defense costs inside or outside the limits, deductibles, limitation of liability clauses, and when $1 million is not enough.
Professional Liability vs General Liability: What Is the Difference?
The difference between professional liability (E&O) and general liability insurance: what each covers, real examples, why general liability excludes professional mistakes, claims-made vs occurrence, additional insured differences, and why most service businesses and client contracts need both.
Tech E&O Insurance for Software, SaaS, and IT Companies
Technology errors and omissions (tech E&O) insurance for software, SaaS, and IT companies in Washington and Idaho: what it covers, how it combines with cyber, what state and client contracts require, limits, claims-made terms, AI features, and common gaps.
Insurance for Independent Contractors, Freelancers, and 1099 Consultants
Insurance for independent contractors, freelancers, and 1099 consultants going out on their own in Washington and Idaho: professional liability (E&O), general liability, cyber, workers comp rules for sole proprietors, what client contracts require, and how coverage moves with you from employee to business owner.
My Contract Requires Professional Liability (E&O) Insurance. What Now?
What to do when a client contract, MSA, or government solicitation requires professional liability or errors and omissions (E&O) insurance: reading the limits, claims-made and tail terms, insurer rating, additional insured, certificates, real Washington and Idaho examples, and how to get covered before work starts.
Professional Liability Insurance for Architects and Engineers
Professional liability (E&O) insurance for architects, engineers, land surveyors, and interior designers in Washington and Idaho: licensing rules, what owner and design-build contracts require, six-year construction claim periods, project policies, tail coverage when you retire, and common gaps.
Insurance for Marketing, Advertising, and Creative Agencies
Insurance for marketing, advertising, design, and creative agencies in Washington and Idaho: professional liability (E&O) for campaigns that miss, media liability for copyright and defamation claims, why general liability may not cover an agency's advertising work, AI-generated content, client data and cyber, and what client contracts require.
Which Professions Must Carry Professional Liability Insurance in Washington and Idaho?
Which professions Washington and Idaho law requires to carry professional liability or errors and omissions (E&O) insurance, or to disclose that they do not: lawyers, real estate licensees, escrow agents, structural pest inspectors, interior designers, and the professions with no requirement, including architects, engineers, CPAs, home inspectors, appraisers, and insurance agents.
Waiver of Subrogation Explained
What a waiver of subrogation is, why contracts and leases require it, how it works on general liability, auto, property, and workers comp, the endorsement you need, how Washington's state-run workers comp changes the picture, and how it differs from waiving workers comp immunity.
Additional Insured Explained
What additional insured means, why clients, general contractors, and landlords require it, the endorsement you need (ongoing and completed operations, blanket or scheduled), why a certificate alone is not enough, primary and noncontributory wording, which policies it applies to, and real Washington and Idaho contract examples.

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