Industry insights

A&E tail coverage: the mistake that ends careers

Architects and engineers carry decades-long liability tails. Skipping or skimping on tail cover at a carrier switch is one of the costliest mistakes in the field.

Tobias Lendl Co-Founder & CTO April 10, 2026

A&E professional liability is claims-made. That distinction sounds technical until you realise what it actually means: the policy that responds to a claim is the policy in force on the day the claim is made — not the day the work was done.

Combine that with the statute-of-repose realities of design and construction defect claims — which routinely surface 5, 10, even 15 years after project completion — and you get the single most consequential decision in A&E insurance: what to do at a carrier switch, a retirement, or a firm closure.

Skip or skimp on tail, and you’ve left every project you’ve ever worked on uninsured.

What “tail” actually is

When you switch carriers (or retire, or close the firm), the new carrier picks up future work. But claims for past work can still be made for years afterwards — and the old carrier’s coverage typically ends when the policy ends, unless you buy an extended reporting period.

That extended reporting period is “tail.” It keeps the old policy responding to claims made after the policy expired, for work done while it was in force.

Standard durations:

  • 1 year — minimum, often inadequate
  • 3 years — common default
  • 5 years — usually recommended for active practitioners
  • Unlimited (or “lifetime”) — appropriate at retirement

Pricing is a multiple of the expiring annual premium: typically 100–250% for a 3-year, 150–300% for a 5-year, 200–400% for unlimited. Yes, it’s a real cost. It’s also smaller than the next claim against your old projects.

Where the mistakes happen

The four scenarios where A&E firms most often get tail wrong:

1. Switching to a cheaper carrier without tail

A firm finds a 30% lower premium. They switch. They don’t buy tail on the expiring carrier. Six months later a claim arrives on a 2019 project. The new carrier excludes prior-acts. The old carrier expired. There’s no coverage.

Fix: when switching, either (a) buy tail on the expiring carrier, or (b) negotiate prior-acts coverage with the new carrier with a retro date going back to your continuous prior coverage. Both work; only one of them happening is essential.

2. Retiring without lifetime tail

A principal retires. The firm closes or transitions. The principal doesn’t buy lifetime tail. Eight years later, an old project becomes a claim. The principal — now retired — has personal exposure with no policy responding.

Fix: lifetime tail is standard at retirement. Some firms negotiate this as part of buyout/succession. Either way, do it.

3. Letting the retroactive date drift

Every claims-made policy has a “retroactive date” — claims for work done before that date aren’t covered. If the date silently moves forward (sometimes happens at renewal under a new carrier), older work becomes uninsured.

Fix: confirm the retro date every renewal. It should be your earliest continuous prior coverage date, not yesterday.

4. Firm acquisitions and ownership changes

When firms merge or get acquired, prior-acts and tail handling is often the last thing negotiated and the first thing that goes wrong. The acquired firm’s old policy may or may not transfer cleanly.

Fix: insurance due diligence on the deal. A specialty A&E broker should be involved before signatures, not after.

What every A&E firm should do this year

  1. Document your retro date and continuous prior coverage. One sheet, kept current. You’d be surprised how many firms can’t produce this.
  2. Confirm tail availability and pricing in writing from your current carrier. Don’t wait until you’re switching.
  3. At any carrier change, decide tail-vs-prior-acts deliberately. Don’t default.
  4. At any ownership change, do insurance diligence. Get the right broker in early.

A&E claims arrive years after the work was done. The cover has to follow. Tail is the mechanism. It’s not optional in any meaningful sense — and the firms that treat it like it is are the ones we see in claim disputes.

Tobias Lendl

Co-Founder & CTO

Tobias started building software at 13. A two-time global hackathon winner, he wrote software for the Austrian government and built systems handling terabytes of satellite data, doing all of this before graduating from Austria's top CS school, HTL Spengergasse. He has since left TU Vienna to build Nomos.

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