Scroll-based Triggering
Display your message after a visitor has scrolled down on your page at least X percent.
Scroll-Based Triggering is an OptiMonk trigger that fires a campaign after a visitor has scrolled past a specified percentage of the current page — from 1% to 100% of the total page height. Where a time-delay trigger fires based on how long a visitor has been on the page, scroll triggering fires based on how far into the content they have gone. This distinction matters: a visitor who has scrolled 60% down a product page has actively engaged with that content — they have read past the hero image, the key features, and potentially the pricing — and is in a meaningfully different state of consideration than a visitor who has simply been sitting on the page for 30 seconds without scrolling. Scroll-Based Triggering is particularly effective for content-heavy pages — long product descriptions, blog articles, landing pages — where scroll depth serves as a reliable proxy for readiness to engage with an offer. The threshold is configurable per campaign, applies to both desktop and mobile (where all navigation is scroll-based), and can be combined with any other targeting conditions and triggers.
Key benefits
- Target visitors who have actually engaged with page content, not just arrived. A visitor who has scrolled halfway down your page has demonstrated active interest in the content they are reading. Firing a campaign at this point — a contextually relevant offer, a content upgrade related to what they are reading, or a discount for the product they have been evaluating — reaches them at a moment of genuine engagement rather than interrupting them before they have seen anything.
- Ideal for long-form pages where time-on-page is a poor engagement signal. On a short homepage, 10 seconds is enough time to read the key message and form an intent. On a long blog post or detailed product page, a visitor might spend 10 seconds or 10 minutes depending on how fast they read. Scroll depth cuts through this variance: a visitor at 70% of a long article has demonstrably consumed a significant portion of the content, regardless of how long it took them to get there.
- Natural, non-disruptive timing that aligns with the visitor's reading pace. A campaign that fires after a scroll threshold appears at the moment the visitor has naturally reached a point in the content where pausing to consider an offer is contextually appropriate — rather than interrupting them at the top of the page before they have had any reason to engage. This produces a less intrusive impression and a higher-intent audience for every campaign impression served.
How it works
In your OptiMonk campaign, click Edit settings and scroll to the Settings summary. Click "Add more triggers" to view all available trigger types. Click the Plus icon next to "On scroll" to add it to the campaign.
Enter the scroll percentage at which you want the campaign to fire — a number between 1 and 100, representing the percentage of the total page height the visitor must scroll past before the trigger activates. For example, entering 50 means the campaign fires when the visitor has scrolled halfway down the page. Choose a threshold that reflects a meaningful level of content engagement for your specific page type — 30–50% for medium-length pages, 50–70% for long-form content.
Select whether the trigger should fire on PC only, mobile only, or both. On mobile, scroll triggering is particularly natural since all interaction is touch-based scrolling. Combine with targeting conditions if needed — for example, scroll trigger + specific page URL to restrict it to blog posts only, or scroll trigger + non-subscriber to target only those who have not yet opted in. Save and publish.
Frequently asked questions
What is Scroll-based Triggering in OptiMonk?+
Scroll-based Triggering is a campaign trigger that fires after a visitor has scrolled past a specified percentage of the page height — configurable from 1% to 100%. It is used to reach visitors who have actively engaged with page content rather than just arrived, and is particularly effective on long-form pages where scroll depth is a more reliable engagement signal than time on page alone.
What scroll percentage should I use?+
The optimal threshold depends on your page type and where in the content the offer becomes most relevant. For a product page, 30–50% typically covers reading past the hero section and key features. For a blog article, 50–70% covers visitors who have read a substantial portion of the content and are likely receptive to a related offer or content upgrade. Testing two different thresholds against each other using OptiMonk's A/B testing is the most reliable way to find the optimal value for a specific page.
Does scroll-based triggering work on mobile?+
Yes. Scroll-based Triggering works on both desktop and mobile and is configurable per device using the device selector in the trigger settings. On mobile, all browsing involves scrolling, making this trigger particularly natural — the campaign fires seamlessly as the visitor scrolls through the page without any behavioral difference from the desktop experience. The device selector lets you apply it to mobile only, desktop only, or both.
Can I combine scroll triggering with a time delay in the same campaign?+
Yes. OptiMonk allows multiple triggers on the same campaign, and the campaign fires when any configured trigger is met first. Combining "On scroll — 40%" with "After 20 seconds" means the campaign fires for visitors who reach 40% scroll depth before 20 seconds, and also for visitors who spend 20 seconds on the page without scrolling that far. This dual-trigger approach broadens the coverage of engaged visitors without requiring separate campaigns.
Does the scroll percentage refer to the page height or the visible viewport?+
The scroll percentage is calculated based on the total page height — 100% means the visitor has scrolled to the very bottom of the page. It is not based on the visible viewport height. This means on a very long page, 50% represents a significant amount of content, while on a short page, the same percentage is reached much more quickly. When setting thresholds, consider the actual length of the target page and how much content a visitor at your chosen percentage would have realistically seen.
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