Some businesses have a longer sales cycle which means it can take longer than 90 days before a lead makes a purchase and becomes a customer. This is usually the case for products or services that have a higher price point and higher levels of complexity.

This makes tracking offline sales conversions difficult, and in some cases impossible, since Google Ads conversion window maxes out at 90 days. 

This means that if the prospect buys 90+ days after they clicked on your Google Ad and became a lead, their sale will not be attributed to your Google Ads account as a conversion.

Even for companies with a sales cycle typically longer than 90 days, they may still receive some sales within that time frame. With Google Search Ads, you’re reaching people actively looking for a product or service like yours, meaning they’re already far down the sales funnel. As a result, you should be able to close a higher percentage of leads within 90 days compared to other lead sources.

If even half or a third of your sales happen within 90 days, I’d still recommend tracking offline sales conversions as your main KPI. This will allow you to optimize your campaign to increase the # of sales that happen within 90 days which should be the focus because it’ll inject the business with more sales revenue faster. 

Your business no doubt doesn’t want to waste time on tire kickers who take months to make a decision and countless man hours by the sales team if you don’t have to. Instead focus on those who are ready to buy now, or within 90 days.

If 80-100% of your sales happen 90+ days after acquiring a lead then you should just set up offline conversion tracking to track marketing qualified leads as your main KPI. You can just calculate how many qualified leads it takes to generate a sale on average to assign a value to the marketing qualified leads.