How long should the deduplication window be before the same person counts as a new lead?
Match the window to your actual repurchase rhythm rather than to a convention. For most home services, something in the thirty-to-ninety-day range catches one person shopping one job without erasing a genuine second job months later. What matters more than the exact number is that one window is chosen, written down, and applied identically in every report and every vendor scorecard.
What the window is really deciding
A dedup window is not a technical setting. It is a judgment about whether two contacts represent the same demand event or two separate ones. A homeowner who calls Monday, gets a quote, calls back Thursday with a question and fills out a form on Saturday is one job. The same homeowner calling in November about a furnace after an August air conditioner repair is two.
Time is a proxy for that judgment, and it is a mediocre one on its own.
Signals stronger than elapsed time
- Same phone plus same service address. The most reliable pair in home services, because addresses are stable and shared across a household.
- Same job type or trade. A plumbing call and an electrical call from one address in the same week are two demand events, not a duplicate.
- An open estimate. If an unaccepted quote exists, a new contact is nearly always follow-up on that quote.
- Same conversation. A call and a web form minutes apart with the same problem description is one person hedging, not two leads.
The two failure modes are not symmetric
A window that is too short inflates lead counts. Cost per lead looks better than it is, booking rate looks worse than it is, and channels that generate a lot of back-and-forth — usually higher-consideration work — get unfairly flattered on volume and punished on conversion.
A window that is too long suppresses genuine repeat demand. That penalizes exactly the channels that bring customers back, and it makes retention-driven revenue disappear into the original acquisition. If your business runs memberships or maintenance plans, an over-long window will quietly hide their value.
Make the choice defensible, then stop arguing
Run a historical quarter through two or three candidate windows and compare the resulting channel rankings. In most accounts the ranking barely moves, which means the window is not worth another meeting. When it does move, you have learned something real about which channel is producing repeat contact.
Whatever you pick, the definition belongs in the report header, not in someone's memory. That is the same discipline behind every reporting system we build, and it is what lets a number survive being challenged. It also removes the most common source of vendor disputes about lead volume.
Topics: deduplication · lead counting · definitions · reporting
Have a version of this question about your own business?
The useful answer usually depends on which systems you run and how they're connected. That's a conversation, not a blog post.