Cyber Insurance Tower Builder
Big programs are not one policy — they are a tower: a retention you keep, then stacked primary and excess layers that each attach where the one below runs out. Build your tower, add the losses a bad year might bring, and watch the layers erode and the attachment points shift. All figures are yours; transparent arithmetic, not insurance advice.
What this builder does
- Build an insurance tower — a self-insured retention plus stacked primary and excess layers — and see each layer’s attachment point and limit.
- Add the losses a bad year might bring and watch the layers erode in turn, attachment points shift, and any loss above the tower fall back on you.
- Transparent arithmetic on figures you enter — nothing fabricated, nothing uploaded.
- Illustrative model for program design, not insurance advice; real towers add reinstatements, differing aggregates and quota-share structures.
Why this matters
Above a certain size, the question stops being "which policy?" and becomes "how do we assemble enough limit, and will it hold up across a bad year?" Buyers tend to think in a single headline limit, but a tower behaves differently: excess layers only engage once those below are gone, and because cyber limits are annual aggregates, a second incident lands on eroded capacity. The gap between the number on the summary and the cover actually standing behind a late-year loss is exactly what this surfaces.
Model your tower against a realistic worst year here, then design the real program — reinstatements, per-layer aggregates, quota shares and all — with your broker. This is an educational model, not insurance advice.
Frequently asked questions
What is an insurance tower?
A tower is how larger organisations assemble more limit than any single insurer will write. At the bottom is a self-insured retention (SIR) or deductible you keep. Above it sits a primary layer, then one or more excess layers, each "attaching" where the layer below it is exhausted — e.g. a $1m primary, then $2m excess of $1m, then $2m excess of $3m, giving $5m of cover above the retention. Each excess layer only pays once the layers beneath it are used up. Towers let you buy large total limits, spread risk across carriers, and shop each layer, but they also create coordination and erosion dynamics that a single policy does not.
What does it mean for a layer to be "eroded"?
Most cyber limits are annual aggregates, not per-claim — so each loss consumes capacity for the rest of the policy period. If a first incident uses up the primary and part of the first excess layer, a second incident that year attaches higher and has less capacity beneath it; a bad enough year can exhaust the whole tower. This is why program design looks at a realistic worst year, not a single loss, and why features like reinstatements (buying back a used layer) exist. This tool models that erosion by applying your losses in sequence and reducing each layer’s remaining capacity.
How much cyber limit should we buy?
There is no universal number — it depends on your data volume, revenue, sector, and the realistic cost of your worst credible year, including ransomware, business interruption, and third-party liability. The sound approach is to size the loss first (using breach-cost benchmarks and your own exposure), then build a tower that covers a bad year with margin, rather than anchoring on a round-number limit. Remember that sublimits and coinsurance can mean the usable limit for a given peril (like extortion) is lower than the tower’s headline. Model both the loss and the recovery before deciding.
Is this a real quote or program design?
No. It is an educational, transparent model that applies your own inputs to show how a tower attaches and erodes. Real programs involve reinstatements, differing per-layer aggregates and definitions, quota-share and co-insurance arrangements, and carrier-specific wordings this tool does not capture. Use it to understand the structure and to reason about adequacy and erosion, then design the actual program with your broker. It is not insurance advice.
This tool is free and always will be. Would a Pro workspace — saved designs, team sharing and exports — be worth paying for?
Show me Pro →No account needed to use this tool — this just tells us whether Pro is worth building out.