How fast should a solar installer respond to leads? What our 4,019-lead dataset shows

Speed-to-lead is one of those ideas everyone in sales agrees with and almost nobody measures on their own data. We run a solar installation company, so we measured ours: every first response to every inbound lead, 4,019 intervals, no trimming of outliers in either direction.

The median first response is 23 seconds. The 90th percentile is 31 seconds. We do not aim at those numbers. They are what an agent with no queue and no shift produces.

The number that changed how we think about staffing is a different one. 55.65% of our leads arrive outside business hours. More than half. Sunday is our single biggest lead day, and it has the least human coverage of any day in this industry. A prospective customer sits down in the evening or at the weekend, when they finally have time to think about their electricity bill, and that is when they start contacting installers.

For most solar companies that means the majority of inbound demand lands in a gap. The lead arrives at nine in the evening, sits until the following morning, and by then the customer has messaged three other companies. Whoever replied first is having the conversation.

The comparison worth making is not average response time but response time by hour. When we split ours, 94.4% of after-hours leads got a reply within 60 seconds against 94.5% during business hours — a difference of one tenth of one percent. Round-the-clock coverage means the reply at 2am is the same as the reply at 2pm. Not that someone is technically on call.

None of this argues that speed wins deals on its own. A fast, useless reply is still useless, and plenty of solar sales are won on trust built over weeks. But speed determines who is in the conversation at all, and a lead that never got a reply cannot be won later by being better.

If you want to know where you actually stand, the measurement is simple and slightly uncomfortable: take your inbound leads from the last month, compute the interval between the customer's first message and your first substantive reply, and look at the median rather than the average. Averages hide the overnight gap. The median tells you what a typical customer experienced.

We ask founding partners to let us measure exactly that before we switch anything on, precisely because the before number is the only thing that makes the after number mean anything.