The news: TikTok advertising is driving delayed returns with ad impact often surging in the second half of campaigns but also persisting after ads stop. The findings from marketing measurement firm Haus challenge brands to rethink measurement windows and campaign timing.

Haus’ geo-based incrementality experiments show TikTok’s measurable lift often remains flat through the first half of a campaign before accelerating sharply. 

Brands across Haus’ TikTok incrementality experiments observed an additional 68% lift to their primary KPI (e.g., sales, revenues, conversions, or new customers) in the post‑treatment window. Experiments averaged 21 days in length.

Why it’s worth watching: Only 33% of CPG brand marketers and agency professionals measure incrementality beyond a basic level, per Skai and the Path to Purchase Institute, leaving most blind to a platform's true delayed returns.

Marketers whose measurement windows do not cover promotional periods may underestimate TikTok’s contribution to sales.

• In one case, an omnichannel brand saw minimal movement for two weeks, with lift accelerating only in the final stretch. Critically, the upward trajectory continued for a week after the campaign ended, including into a subsequent promotional period, per Haus.
• For a direct-to-consumer (DTC) brand with products priced above $400, almost all impact was concentrated in the final three days of a month-long experiment, coinciding with a promotion. 
• Haus suggests the ads warmed up audiences during the treatment window, with conversions spiking later in the campaign.

Implications for brands: Haus’ experiments reveal that TikTok functions as a demand-building layer, not a direct-response shortcut. Here are ways brands can yield more predictable results:

• Lengthen measurement windows. Don’t cut off reporting at the campaign end date. Track at least 1–2 weeks post-flight to capture delayed lift.
• Run longer campaigns. Short bursts may show flat results; give TikTok time to warm up audiences, especially for higher-price-point products.
• Align promotions strategically. Use TikTok’s early campaign phase to boost awareness and intent, then time promotions to harvest that demand in the back half or immediately after.

Brands that optimize their campaign timing and measurement to account for TikTok’s characteristic delayed impact could capture returns that shorter-sighted competitors completely miss.

This content is part of EMARKETER’s subscription Briefings, where we pair daily updates with data and analysis from forecasts and research reports. Our Briefings prepare you to start your day informed, to provide critical insights in an important meeting, and to understand the context of what’s happening in your industry. Non-clients can click here to get a demo of our full platform and coverage.