Google Analytics 4 (GA4) provides unparalleled depth of insight into how users interact with your website and app, but its terminology can sometimes be confusing. The two most important reports for marketers—the User Acquisition report and the Traffic Acquisition report—often look similar but serve two different, indispensable purposes.
Understanding the fundamental differences between these two reports is the key to accurately evaluating your marketing campaigns, optimizing budget allocation, and creating a cohesive view of the customer journey. It all depends on the basic concept of scope and attribution.
This guide will uncover the secrets of these twin reports, explaining their unique focus, the dimensions they use, and how to leverage both for an overall marketing strategy.
The Core Difference: Scope and Focus
The simplest way to distinguish between the two reports is by understanding what they are measuring:
| Feature | User Acquisition Report | Traffic Acquisition Report |
| Primary Scope | User (Individual Person) | Session (Individual Visit) |
| Primary Focus | New Users Only (The user’s first-ever visit) | All Sessions (New and Returning Users) |
| Goal | Understand how new customers find and land on your site for the first time. | Understand how all users are engaging across all sessions and which channels drive overall traffic volume. |
| Attribution | Uses the First-Touch Attribution model. | Uses the Last-Touch Attribution model (specifically, the first source within that session). |
| Key Dimension Prefix | First user (e.g., First user source, First user medium) | Session (e.g., Session source, Session medium) |
The core takeaway is this: User Acquisition tracks the start of the customer relationship, while Traffic Acquisition tracks the performance of every single visit.
Understanding the Scope: User vs. Session
The difference in scope is the root cause of the data disparity between the two reports.
1. User-Scoped Data (User Acquisition)
A user is a person (or, more accurately, in GA4, a unique device/browser/ID). The User Acquisition report looks at the first interaction that a person has with your website or app.
- Scenario: A user sees and clicks on a Facebook ad for your product, and makes their first visit.
- Tracking: GA4 records the channel that brought them here – in this case, Facebook/CPC.
- Scope: This first touchpoint is permanently tagged to the user’s ID for their entire lifetime in your GA4 property. Every subsequent event and conversion made by the user, even years later, will be submitted back to Facebook/CPC in the user acquisition report.
This report is vital for assessing the effectiveness of your top-of-funnel acquisition campaigns and understanding which channels are best at introducing your brand to new audiences.
2. Session-Scoped Data (Traffic Acquisition)
A session is a single visit or a period of continuous interaction of a user with your website or app. A single user can have multiple sessions. The Traffic Acquisition report looks at the traffic source for each session.
- Scenario: The user from the previous example returns to your site a week later after clicking a link in an email newsletter.
- Tracking: GA4 records the channel that brought them to this specific visit – in this case, email/newsletter.
- Scope: Only this specific session and the events within it are credited to the email/newsletter in the traffic acquisition report. If they return later by directly typing your URL, that session will be attributed (direct) / (none).
This report is important for measuring the performance of remarketing, re-engagement, and ongoing content strategies, allowing you to see which channels are driving volume and immediate engagement right now.
The Attribution Models in Practice
The difference in scope dictates the attribution model used by each report.
1. User Acquisition: The First-Touch (First-Click) Model
The User Acquisition report uses the first-touch (or first-click) model. This means that 100% of the credit for acquiring that user goes to the first channel they interacted with.
- Focus: Answering the question, “Which channel deserves credit for opening the door?”
- Data: When you look at conversions in the User Acquisition report, you’re looking at conversions that occurred at any time in that user’s lifetime, but have been credited back to the original acquisition channel.
- Example: A user first finds you through Google organic search and purchases something a month later via an email link. User acquisition reports attribute the conversion to Google organic search.
2. Traffic Acquisition: The Session-Start (Last-Click) Model
The traffic acquisition report uses the session-initiation model. While GA4 offers different attribution models for ad sections, the acquisition report defaults to crediting the channel that initiated the specific session you’re watching. For all intents and purposes, it serves as the last-click model for that session.
- Focus: Answering the question, “Which channel deserves credit for driving this specific journey?”
- Data: When you look at conversions in the Traffic Acquisition report, you’re looking at conversions that occurred in a specific session, attributed to the channel that initiated that session.
- Example: The same user from the previous example purchases something through an email link. The traffic acquisition report attributes conversions to sessions and email links.
Using the Right Report for the Right Question
Choosing between the two reports depends entirely on your marketing objective:
🎯 Use the User Acquisition Report When You Want To:
- Evaluate long-term ROI: Determine which initial campaigns (e.g., brand awareness, cold audience ads) bring in new users who ultimately convert and become high-value customers.
- Optimize budget for growth: Find out which channels are the most effective customer acquisition engines. If your goal is to grow your customer base, this is your primary report.
- Analyze new user behavior: Look at early engagement metrics (e.g., bounce rates, engagement sessions), especially for those new to your brand, which indicate the quality of your onboarding experience for first-time visitors.
📈 Use the Traffic Acquisition Report When You Want To:
- Measure campaign performance: Determine the immediate impact and total traffic volume generated by short-term campaigns like holiday email blasts or new retargeting ads.
- Evaluate re-engagement: Understand how well your remarketing and loyalty programs (e.g., emails, push notifications) are working to bring existing users back to the site for a second session.
- Analyze overall channel health: Get a holistic view of total site traffic and understand which channels drive the most visits, whether the user is new or returning. It is useful for content optimization and SEO strategies.
Key Dimensional Differences
The dimensions used in each report clearly reflect their scope, making it easy to identify which one you are viewing:
| User Acquisition Dimensions (User-Scoped) | Traffic Acquisition Dimensions (Session-Scoped) |
| First user default channel group | Session default channel group |
| First user source | Session source |
| First user medium | Session medium |
| First user campaign | Session campaign |
Notice the key prefix: First user for the acquisition touchpoint that is sticky to the user’s ID, and Session for the touchpoint that started the current visit.
Conclusion: A Harmonious Relationship
User acquisition and traffic acquisition reports are not competitive; They are complementary tools that provide two parts of the complete customer journey story.
- User Acquisition (“Hunter”): Shows which channels successfully seek out and capture new customers. It tells you where to invest for growth.
- Traffic Acquisition (“Nurturers”): Shows which channels successfully nurture existing users and drive ongoing engagement. It tells you how to optimize for volume and instant conversions.
By using both reports together, you move beyond a simple count of visits to a sophisticated understanding of your audience: who they are, where they come from, and how your continued marketing efforts keep them coming back. This dual perspective is essential to mastering GA4 and creating a truly data-driven marketing strategy.