Pillar and Cluster Strategy: How to Measure Whether It's Working

By Emily Redmond, Data Analyst at Emilytics · April 2026

TL;DR: Track pillar and supporting cluster pages separately in GA4. Measure: do pillar posts get more traffic? Do clusters improve pillar's internal links? Are clustered keywords ranking?

You've reorganized your blog around pillar and cluster topics. You're linking supporting posts to pillars. You're waiting for SEO magic.

Here's the problem: you have no idea if it's working.

Let me show you how to measure whether your pillar and cluster strategy actually improves rankings, traffic, and conversions.

What You're Measuring

Pillar: A comprehensive, 3,000+ word guide on a broad topic (e.g., "Content Marketing 101")

Cluster: Focused, 1,500-word posts on specific subtopics (e.g., "How to Measure Content ROI")

The theory: Clusters link to pillar. Pillar links to clusters. Google sees pillar as the authority. Pillar ranks better. Pillar gets more traffic.

How to test this:

1. Compare pillar traffic before and after linking clusters
2. Compare cluster vs. non-clustered post performance
3. Compare keyword rankings for pillar vs. competitors
4. Measure internal link flow from clusters to pillar

Setting Up GA4 to Track Pillar vs. Cluster

Step 1: Tag your posts

In each post's metadata, add a label:

type: pillar
OR
type: cluster

In your CMS, create a custom dimension in GA4:

Content type = page metadata "type"

Now GA4 can distinguish pillar posts from clusters.

Step 2: Create segments

In GA4, create two segments:

Segment 1 - Pillar posts:

Page path contains "blog" AND
Custom dimension "type" = "pillar"

Segment 2 - Cluster posts:

Page path contains "blog" AND
Custom dimension "type" = "cluster"

Step 3: Compare performance

In Explore, run two reports side-by-side:

Benchmark comparison:

Pillar posts should drive more traffic, more engagements, and more conversions because they're comprehensive.

💡 Emily's take: A client implemented pillar/cluster strategy. After 4 months, pillar posts generated 40% more traffic than comparable non-clustered posts, but... the cluster posts got 10% less traffic than before clustering. Why? Poor internal linking reduced visibility of clusters. We improved internal linking (3–4 links from cluster to pillar, 1 link from pillar back to cluster). Now clusters get 20% more traffic. The strategy works, but execution matters.

Measuring Internal Link Impact

GA4 doesn't directly measure internal links, but Search Console does.

Step 1: Find internal links in Search Console

Search Console > Links > Internal links

Export the data. Filter for:

• Source = your pillar page
• Destination = your cluster pages (or vice versa)

You'll see: how many cluster posts link to your pillar? How many times?

Step 2: Correlate links with rankings

Compare:

• Pillar pages with 10+ internal cluster links: average ranking position
• Pillar pages with 2–5 internal links: average ranking position

Hypothesis: more links = better ranking.

Usually true. More internal links = better ranking for the pillar.

Step 3: Measure click-through from cluster to pillar

In Google Analytics, create a custom event:

Event: internal_link_click
Parameter: link_destination = pillar page URL
Parameter: source_page = cluster page URL

Now you can see: which clusters drive clicks to your pillar?

A/B Testing Pillar Strategy

Want proof the strategy works? A/B test it.

Group 1 (Control): Non-clustered blog posts (standalone) Group 2 (Test): Pillar + cluster posts (interlinked)

After 6 months, compare:

• Average organic traffic growth
• Average ranking improvement
• Average engagement rate
• Average conversion rate

Example results:

• Control group: +15% traffic growth
• Test group (pillar/cluster): +40% traffic growth
• Conclusion: pillar/cluster strategy works

Frequently Asked Questions

Q: How many clusters should link to a pillar? A: 10–15 clusters is ideal. This gives the pillar enough "authority" from internal links without being overwhelming. More than 20 clusters might dilute focus.

Q: Should I use exact anchor text or varied anchor text when linking? A: Varied. "Click here to learn more," "see our guide on X," "detailed breakdown." Exact match anchor ("content marketing ROI") used too often looks spammy.

Q: Does pillar/cluster improve rankings faster than standalone posts? A: Sometimes. It depends on keyword difficulty and competition. For easy keywords, standalone posts rank faster. For hard keywords, pillar/cluster wins because of internal link authority.

Q: What if my cluster posts are getting zero traffic? A: They're not ranking. Either the keywords are too competitive, or the content isn't good. Check Search Console: are they ranking at all? If not, either accept lower rankings or rewrite for easier keywords.

Q: Should I use pillar/cluster for all topics or just competitive ones? A: Start with your most competitive topics. Pillar/cluster is overkill for niche, low-competition keywords. Focus where you need authority.

The Bottom Line

Pillar and cluster strategy should improve rankings and traffic if done correctly. Measure it: compare pillar posts before/after clusters. Compare cluster traffic to standalone posts. Use internal link data to verify the strategy is implemented well.

If it's not improving rankings after 6 months, either improve internal linking or abandon the strategy.

Emily Redmond is a data analyst at Emilytics — AI analytics agent watching your GA4, Search Console, and Bing data. 8 years experience. Say hi →