If you're offering insurance to your customers, attach rate is the single number that tells you how well it's working. It's also the number most partners measure loosely or not at all. This guide covers what attach rate really is, how to calculate it without fooling yourself, and the concrete levers that move it.
What is insurance attach rate?
Attach rate is the percentage of eligible customers who actually buy insurance through your offer. It answers a simple question: of the people who could have taken coverage at the relevant moment, how many did?
The basic formula is:
Attach rate = bound policies ÷ eligible customers
The word that does the heavy lifting is eligible. Attach rate isn't measured against your entire customer base — it's measured against the people who actually hit the insurable moment. Get the denominator wrong and the number becomes meaningless.
How do you calculate it correctly?
Most attach-rate mistakes come from a sloppy denominator. Be deliberate about who counts as eligible.
- Define the insurable moment. Decide exactly which event makes a customer eligible — a vehicle purchase, a lease signing, a completed checkout.
- Count eligible customers in a period. How many people hit that moment in the month or quarter?
- Count bound policies in the same period. Use bound policies, not clicks or quotes — coverage actually in force.
- Divide and track over time. One snapshot tells you little; the trend tells you everything.
A worked example makes it concrete:
Metric | Value |
|---|---|
Eligible customers | 1,000 |
Customers who quoted | 300 |
Policies bound | 120 |
Attach rate | 12% |
Note that quote rate (30%) and attach rate (12%) are different metrics. Tracking both tells you where you're losing people — at the offer, or inside the quote flow.
What's a good attach rate?
There's no universal benchmark, and you should be skeptical of anyone who quotes a precise "industry standard." Attach rate depends heavily on:
- How relevant the coverage is to the moment. Renters insurance at lease signing attaches far better than an unrelated add-on.
- How required or expected the coverage is. Some moments practically demand insurance; others are optional.
- How frictionless the experience is. A fast, pre-filled flow attaches better than a clunky redirect.
The right benchmark is your own trend line. A rising attach rate against a stable definition of eligibility is the signal that matters, regardless of where you started.
What actually drives attach rate up?
A handful of levers reliably move the number. In rough order of impact:
- Timing. Offer coverage at the exact moment of need, not before and not as an afterthought. Relevance peaks at the insurable moment.
- Relevance. Match the coverage to what the customer is doing. The closer the fit, the higher the attach.
- Placement. Put the offer where the customer's attention already is — in the checkout, the dashboard, the onboarding step — not buried in an email.
- Friction. Every extra field, click, or redirect costs you conversions. Pre-fill what you already know.
- Speed. A quote-and-bind that takes minutes keeps customers from cooling off. Truvo quotes and binds in minutes, which directly supports attach.
- Framing. Plain-language copy that explains why this coverage, why now outperforms generic prompts.
You rarely lift attach rate with one big change. It's usually several small improvements — better timing, less friction, clearer framing — compounding together.
How do you diagnose a low attach rate?
When the number disappoints, resist the urge to guess. Split the funnel and find the leak.
- Are eligible customers even seeing the offer? If impression rate is low, it's a placement and visibility problem.
- Are they starting a quote? A low quote rate points to weak relevance or framing at the offer itself.
- Are quotes converting to bound policies? A drop here is a friction or experience problem inside the flow.
- Is attribution accurate? Make sure bound policies are being counted and credited correctly, or your attach rate will read artificially low.
Your partner dashboard is the starting point for this — it shows referrals moving from lead to quoted to bound, so you can see exactly which stage is leaking.
How does a deeper integration affect attach?
Integration depth and attach rate are linked. A bare referral link can convert well for occasional moments, but for high-volume, in-product moments a more native experience usually attaches better because it removes the handoff and pre-fills data.
- Refer — Good for testing and occasional moments; the redirect adds a little friction.
- Embed — A co-branded hosted flow keeps continuity and lifts trust.
- API — Native quoting with pre-filled data typically attaches best at volume.
The trade-off is effort, so let the numbers lead: if a high-traffic moment shows healthy attach on a referral link, deepening the integration often pushes it higher.
Measured honestly and watched over time, attach rate becomes your clearest signal of how much revenue your insurance offer is really producing — and your roadmap for getting more. See how it works or become a Truvo partner to start tracking attach with a dashboard built for it.