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Two professional liability policies can look identical on the declarations page and behave very differently when a claim arrives three years from now. The difference is the trigger. Professional liability insurance, also called errors and omissions or E&O coverage, is usually sold on a claims made basis. Some other liability policies are sold on an occurrence basis. Which trigger your policy uses decides whether an old project can still produce a covered claim long after the work was delivered.
The occurrence trigger, in plain terms
An occurrence policy responds to incidents that happen during the policy period, whenever the claim is eventually filed. If the work, the advice, or the accident took place while the policy was in force, that policy is the one that answers, even if the client sues years later and you have since changed insurers or closed the business.
General liability insurance for bodily injury and property damage is commonly written this way, which is why businesses are used to the idea that last year’s policy covers last year’s events. Our comparison of general liability and professional liability explains how the two policies divide the work, and the trigger difference is part of that divide.
The claims made trigger, in plain terms
A claims made policy responds to claims that are made against you during the policy period, for work done after a date printed in the policy called the retroactive date. Two conditions have to line up. The claim must arrive while the policy is active, and the work that caused it must fall after the retroactive date.
Most professional liability and E&O policies work this way. Insurers prefer it because it closes their books on a policy year once the year ends, instead of leaving them exposed to claims that surface a decade later. That preference shapes the price. Our guide to professional liability insurance cost factors covers the pricing side, and the claims made structure is one reason first year premiums often start lower and climb over the first several renewals, a pattern insurers call step rating, as the policy picks up exposure for more past work.
The retroactive date is the number to protect
When you first buy a claims made policy, the retroactive date is usually set at the start of that policy, or at the date you first held continuous coverage. Work you did before that date is outside the policy, even if the claim arrives tomorrow.
This makes switching insurers a delicate operation. If you move to a new carrier and accept a fresh retroactive date, every project you completed before the move loses its coverage for future claims. The correct way to switch is to carry the original retroactive date forward onto the new policy, which insurers call prior acts coverage. Verify it in writing on the new policy documents. A cheaper quote built on resetting the date is not cheaper in any sense that matters.
Gaps in coverage break the chain the same way. Letting a claims made policy lapse and buying a new one later usually means the new policy starts with a new retroactive date, and the work from the gap years is uninsured for claims that arrive afterward.
Tail coverage: insuring the past after you stop
Retirement, selling a practice, or closing a firm creates a problem unique to claims made policies. The work is finished, but claims about it can still arrive for years. An extended reporting period endorsement, known as tail coverage, extends the window in which claims can be reported for work done before the policy ended.
Tail coverage is bought once, usually within a short window after the policy ends, and its price is commonly expressed as a multiple of the expiring annual premium. It does not cover new work. It only keeps the door open for claims about old work. Some policies include a free tail under set conditions, such as retirement after a minimum age and years of continuous coverage with that carrier. Read those conditions early in your career rather than the year you plan to stop, because qualifying for them can influence which carrier you stay with.
The mirror image exists for buyers of a business or professionals joining a new firm, where prior acts coverage on the new policy, sometimes called nose coverage, picks up the past work instead. One of the two mechanisms has to cover every year you practiced. A year with neither is a year you are self insuring without having chosen to.
Questions to ask before you sign or switch
Ask what your retroactive date is and get it confirmed on the policy, not in an email summary. Ask how a switch would treat that date. Ask what the tail would cost if you stopped practicing at the end of this term, and what conditions would make it free or discounted. Ask how quickly claims must be reported, since claims made policies often require notice within the policy period or a short grace window after it, and a client complaint you sit on can become an uninsured claim through delay alone.
The premium differences between E&O quotes get most of the attention at buying time, and our overview of who needs professional liability insurance and what it costs covers that ground. The trigger and the date are quieter details. They are also the ones that decide, years from now, whether the policy you paid for is standing there when a claim finally arrives.
