7-day click
Crediting an ad with any conversion that happens within seven days of a click on it.
Meta’s default, usually paired with a one-day view window. Someone clicks on Monday and books on Saturday, and the ad gets the credit.
Why it matters for HVAC
Seven days is a defensible window for a considered purchase and a generous one for an emergency call-out. A homeowner who clicked an ad about system age on Monday and called you on Saturday about a failure that happened Friday night is being credited to advertising that may have had nothing to do with it.
The longer the window, the more of your existing demand the channel absorbs credit for. This is the single largest reason Meta-attributed conversions exceed what a business can actually trace.
How it is measured
Request it explicitly when pulling reports and print it beside the number. Comparing the same period on seven-day click against one-day click shows you how much of the reported result depends on the setting rather than on the work.
A worked example
A month reports 52 conversions on seven-day click. On one-day click the same period shows 29. Neither number is wrong. The 23 in between are people who clicked, did nothing for a while, and eventually converted, and whether the ad caused that is precisely the question a holdout test exists to answer.
These figures are invented to show the arithmetic. They describe no real business.
Where this is demonstrated
The Tracking and the Conversions API pillar scores every listed agency on what they document here, and gives you the questions that tell you which one you are being sold.