How to Compare SEO vs Paid Search Performance in Google Analytics
· 10 min · Data Analysis
SEO and paid search can look “better” depending on what you measure. This guide shows how to compare them fairly in Google Analytics and act on the results.
Why comparing SEO and paid search is tricky (and worth it)
SEO (organic search) and paid search (PPC) often get judged with different standards. SEO is usually evaluated on traffic growth and non-branded visibility, while paid search is judged on efficiency (CPA/ROAS) and immediate conversions. If you compare them without aligning definitions, attribution, and conversion value, you’ll end up optimizing the wrong channel.
A fair comparison helps you: • Decide where the next dollar (or hour) should go • Spot cannibalization (paid clicks replacing organic clicks) • Identify landing pages that work in both channels • Improve conversion rate and lead quality, not just traffic
To do this well, you need to compare channels on the same outcomes (conversions and value) and also understand their different roles in the customer journey.
Set up Google Analytics for an apples-to-apples comparison
Before you open any report, make sure your data is clean. Most “SEO vs PPC” debates are actually tracking and attribution problems.
Choose your analytics version and align definitions
This article focuses on GA4 (the current standard). If you still use Universal Analytics exports, the logic is similar, but report names differ.
In GA4, the key channel groupings are: • Organic Search for SEO • Paid Search for PPC search ads (Google Ads, Microsoft Ads, etc.)
Make sure your paid traffic is not leaking into Organic or Direct.
Step 1: Ensure paid search tagging is correct
If you use Google Ads, enable auto-tagging (adds gclid). For non-Google paid search (e.g., Microsoft Ads), use UTM tags: - utm_source=bing - utm_medium=cpc - utm_campaign=brand_search (or similar) - Optional: utm_term={keyword}
Benchmarks to sanity-check: • If you run active search campaigns, Paid Search sessions should not be near zero. • If paid search spend is significant, Paid Search should rarely be under 5% of total sessions unless budgets are tiny or tracking is broken.
Step 2: Confirm channel grouping is classifying correctly
In GA4: Go to Reports → Acquisition → Traffic acquisition Use the primary dimension Session default channel group Confirm you see both Organic Search and Paid Search
If traffic is misclassified, check: • Missing UTMs on paid links • Redirects stripping query parameters • Cross-domain issues
Step 3: Use consistent conversions and values
To compare channel performance, you need consistent outcomes: • Key events (GA4 conversions) such as purchase, lead form submit, quote request, demo booking • Revenue for ecommerce, or assigned lead value for lead gen
For lead gen, assign realistic values. Example: • Lead form submission value: $50 • Qualified lead (SQL) value via CRM import: $300 • Closed deal value: actual revenue
Actionable rule: • If you can’t import offline outcomes yet, start with a conservative expected value per lead based on historical close rate.
Build the core reports to compare SEO and paid search
You can do a lot directly in GA4, but for a clean comparison, you should use a small set of consistent views.
Report 1: Channel performance overview (sessions, conversions, value)
In Traffic acquisition: • Primary dimension: Session default channel group • Filter to Organic Search and Paid Search • Add columns for: - Sessions - Engaged sessions - Engagement rate - Key events (conversions) - Session key event rate - Total revenue (or total conversion value)
What to look for: • Conversion rate gap: Paid Search often converts higher on last-click, especially for brand and high-intent keywords. • Value per session: A strong single metric to compare efficiency when conversion values are set.
Realistic benchmarks (will vary by industry): • Ecommerce: - Organic Search session conversion rate: 0.8%–2.5% - Paid Search session conversion rate: 1.2%–3.5% • B2B lead gen: - Organic Search lead rate: 0.5%–2.0% - Paid Search lead rate: 1.0%–4.0%
If your paid conversion rate is lower than organic, it’s not automatically bad—your paid campaigns may be targeting higher-funnel queries, or your landing pages may not match intent.
Report 2: Landing page comparison by channel
Landing pages reveal whether performance differences come from: • Audience intent (channel effect) • Page quality and message match (landing page effect)
In GA4: Go to Reports → Engagement → Landing page Add a comparison (filter) for Session default channel group = Organic Search Repeat for Paid Search (or use Explore)
Key metrics: • Sessions • Key event rate • Revenue / conversion value
Actionable pattern: • If the same landing page converts well for paid but poorly for organic, SEO traffic may be less qualified (query mismatch) or the snippet may be attracting the wrong intent. • If it converts well for organic but poorly for paid, your ad targeting or ad copy may be misaligned.
Report 3: New vs returning users (channel quality)
SEO often drives more first-time discovery; paid search often captures demand. Compare bot…