Google Ads Attribution Models in 2026: A Complete Guide

Do you know what Google Ads Attribution models are, which ones Google currently supports, and how they work? 

If not, then you are in the right place. 

Through this blog, we will explore Google Attribution models in detail. We will cover the different types (i.e., last-click and data-driven), the models Google previously supported (first click, linear, time decay, etc.), how to change attribution models, their impact on bidding strategies, and which one you should choose for your ads. 

So, are you ready? Let’s quickly start then. 

What is Attribution Model in Google Ads?

Attribution models in Google Ads allow you to decide how much credit each ad interaction gets for your conversions. They enable you to understand how different touchpoints influence a customer, before they complete a desired action (such as making a purchase). 

Essentially, users often click multiple ads from the same advertiser before they complete a conversion. Each interaction plays an important role in shaping their final decision. Attribution models help you measure that role clearly. They measure the impact of each click across the entire conversion journey. 

So, instead of assigning credit to the last click, you can distribute the credit across several interactions using the appropriate attribution model. This would provide you with a clearer view of campaign performance and help you understand which keywords, ads, and campaigns are driving real results for your business. 

And when you evaluate ad performance more accurately, you can optimize it with more confidence, allocate budget more smartly, and achieve a stronger return on ad spend! 

Explore: What is Veo in Google Ads.

Benefits of Using Google Ads Attribution Models 

With better control over conversion credit, you can make smarter marketing and business decisions, such as: 

1. Reach customers earlier in their conversion journey: Attribution models are helpful for understanding which ad campaigns introduce your brand to your target audience. By identifying these touchpoints early and accurately, you can invest in awareness campaigns more effectively. This can help you move users from discovery to purchase more quickly. 
2. Match the model to your business goals: You can use two different Google attribution models for your ad campaigns. This gives you the flexibility to align reporting with your sales cycle, marketing objectives, and specific business needs. 
3. Improve your bidding strategy: With detailed and smarter insights into campaign performance, you can optimize your bids better. 

Example: If you find that certain keywords are leading to more purchases for your online shoe store through the “Data-driven” attribution model, you can raise your bids for them. 

What are the Different Attribution Models in Google Ads: List of Active + Deprecated Ones 

Here’s a concise version: There are six types of Google Ads attribution models: last-click, first-click, linear, time decay, position-based, and data-driven. Each model distributes credit for conversions differently, allowing you to understand how each touchpoint impacts your customer journey.

Additionally, along with the model’s definition, we will discuss its mechanics, statistical assumptions, biases and pitfalls, and use cases. 

1. Last Click Attribution Model

Last click gives 100% credit of the conversion to the last-clicked ad and its corresponding keyword in the user journey. 

1. Status in Google Ads: Google currently supports the last click attribution model. 
2. Statistical Assumptions: This model assumes that the last click leads to the conversion. It treats prior ad interactions as non-influential, which is a strong behavioral assumption, as it ignores assisted interactions.
3. Biases and Pitfalls: The last-click bias gives more credit to brand search and remarketing campaigns, which usually target users at the bottom of the funnel.  

It gives little to no credit to prospecting and awareness-generation (Display, Video, or even Search) campaigns that operate at the top of the funnel. This can make upper funnel campaigns look inefficient when they might be driving demand for your business.     

4. Best Suited For: Use this model if your business has shorter sales cycles and fewer touchpoints, and if your target audience makes quick decisions.

Example: Ecommerce stores that sell low-cost, impulse purchase products, where customers may see a single ad and complete checkout.  

2. Data-Driven Attribution Model

Data-driven attribution model assigns credits for a conversion based on past data for that particular conversion action. It differs from other models in that it analyzes your account data, including clicks and video engagement across Search, YouTube, and other campaigns, to calculate how much each ad interaction contributed to the conversion. And based on that, it assigns credits to relevant ads and keywords.  

1. Status in Google Ads: Currently supported in Google Ads. 
2. Statistical Assumptions: This model assumes that past behavior can be helpful to predict future conversions and that patterns in conversion pathways show real impact. However, it doesn’t fully prove cause and effect. True incrementality requires controlled lift testing.
3. Biases and Pitfalls: 

• Data-driven attribution model can favor those channels that have better conversion tracking. For example, Search campaigns with clearer click data compared to upper funnel campaigns. 
• Also, changes in conversion tracking quality can lead to credit shifts between campaigns. 
• Privacy limits and modeled conversions can also affect available data. 
• Lastly, if conversion volume is low, the model may not perform reliably. In some cases, results may look similar to the last click.

4. Best Suited For: Leverage this Google Ads attribution model if: 

• Your business has a complex conversion path with multiple touchpoints involved. 
• You have past conversion data in abundance for Google’s machine learning algorithms.
• And you run Search, YouTube, Display, and Shopping campaigns together.

3. First Click Attribution Model

First click gives 100% conversion credit to the initial ad click or interaction in a user’s journey, and ignores all other subsequent touchpoints. 

1. Status in Google Ads: Google no longer supports this attribution model. It is deprecated.  
2. Statistical Assumption: This Google attribution model assumes that the first ad interaction creates the entire demand and is responsible for driving the conversion as well. It treats nurturing or conversion-completion interactions as non-influential. 

In essence, just like the last-click model, it operates on a strong assumption about user behavior. 

3. Biases and Pitfalls: First, click over credits awareness and prospecting campaigns, and under credits brand search, remarketing, and other bottom-of-the-funnel ad campaigns. 

This can lead to inflated values at the top of your marketing funnel and divert your attention from issues that might actually exist in the conversion process. 

4. Best Suited For (Earlier): When your goal was to measure the effectiveness of your awareness and brand discovery campaigns. 

Though it was never considered ideal for bidding or direct response optimization. 

4. Linear Attribution Model

The Linear attribution model distributes credit for a conversion equally across all clicks in the path. 

1. Status in Google Ads: Not supported anymore by Google.  
2. Statistical Assumption: At its core, this model assumes that every interaction (click) contributes equally to a conversion. However, in reality, some clicks always influence users more than others. 

Though the model serves as a useful neutral baseline for comparison. 

3. Biases and Pitfalls: In this model, certain low-intent interactions can mistakenly get more credit than they deserve. Similarly, some high-value interactions that actually influenced a user to complete the conversion may not get the credit they deserve. 

Plus, it can also spread the credit too wide in longer buyer journeys. This can reduce the apparent value of important touchpoints in complex conversion paths (sales cycles). 

4. Best Suited For (Earlier): Marketers used this model whenever they wanted a balanced view of the entire buyer journey, and a middle ground between the first and last click. 

However, this model was not ideal for optimizing bids. 

5. Time Decay Attribution Model

Time decay assigns more credit to ad interactions that happen closer in time to the conversion. It follows a 7-day half-life to distribute credit. So, a click that occurred 8 days before a conversion would get half as much credit as a click that occurred 1 day before the conversion. 

1. Status in Google Ads: Time Decay is no longer available for use in the Google Ads interface. 
2. Statistical Assumption: This model assumes that recent interactions or clicks have a stronger influence on conversions and that the seven-day half-life aligns with your buying cycle. 
3. Biases and Pitfalls: Even time decay favors BoFu campaigns more, as they play a greater role in influencing a user’s decision and lead to clicks closer to the buyer’s end of the journey. 

It undervalues ad campaigns that cater to users at the top of your marketing funnel. 

4. Best Suited For (Earlier): Businesses with long sales cycles and the belief that recent engagement mattered most often used this model. 

6. Position-based Attribution Model

The Position-based Google Ads attribution model gives 40% credit to both the first and last clicked events. The remaining 20% is distributed evenly across other clicks along the conversion path. 

1. Status in Google Ads: No longer available for use. 
2. Statistical Assumption: This model assumes that the first ad interaction (click) creates demand while the last one closes the sale. Other clicks that occur throughout the buyer journey play a small, supportive role.
3. Biases and Pitfalls: Position-based attribution can assign unnecessary credit to awareness campaigns even if their real-world impact is limited. It can also give extra credit to conversion-closing channels, even when their impact is not significant (e.g., journeys with heavy remarketing). 

As the model is rule-based, it does not adjust to real user behavior. 

4. Best Suited For (Earlier): Businesses that want to value both brand discovery and sales closing advertising efforts. 

Attribution Models For Conversions and Bidding

The “Attribution model” setting applies only to conversion actions in Google Ads. You can use these models for website and Google Analytics conversion actions. 

So, essentially, you can choose an attribution model for any individual conversion action and control how the credit for conversion is distributed for that specific goal. This also means that different conversion actions can use different models depending on your specific business needs. 

Also, any selected Google attribution model affects how conversions are counted in the “Conversions” and “All conversions” columns. And this is why it also affects the specific bidding strategy that uses the data in that “Conversions” column. So, if you are using an automated bidding strategy such as Target CPA, ECPC, etc., the attribution model will have an impact on how your bids are optimized. 

Note: Whenever you change the attribution model, the credit will also be split across different campaigns and keywords. As a result, certain key performance metrics such as CPA and RoAS may also change.

If you are currently using a manual bidding strategy, you can always change your attribution model to configure and optimize your bids more effectively. 

How to Set and Change Google Ads Attribution Model? 

We will now discuss how you can set and edit a conversion action’s attribution model in Google Ads. 

Setting Attribution Model 

You can set the attribution model of a conversion action while creating it. Here’s how: 

1. Go to “Goals” from the left-hand side menu in your Google Ads account. 
2. Select “Conversions,” and click on “Summary.” 

3. Scroll down to “All your goals” and there you will see the option to “+ Create conversion action.” Click on it. 
4. First, select a category for which you want to create conversions. 
5. Click on ‘+ Create conversion.’ 
6. Select a data source. For example, we will choose ‘Calls from ads.’ 

Bonus: Read our blog on Google Ads call tracking.

7. Once the conversion is created, you can click on “Edit Settings.”

8. There, you will see all the settings such as ‘‘Action optimization,’’ ‘‘Value,’’ etc., including “Attribution.” 
9. Click on it and select a model from “Data-driven” and “Last click.” 

💡Please note that, by default, Google assigns the “Data-driven” model to all conversion actions.

10. Click on ‘Done’ and finish the remaining steps of the Conversion action creation flow. 

Editing an Existing Google Ads Attribution Model

To edit the existing attribution model of a conversion action, here’s the step-by-step process that you can follow:

1. In your Google Ads account, go to “Goals,” then “Conversions,” and “Summary.”
2. Scroll down to “All your goals,” and there you will find all the categories of conversion actions that exist within your account. For example, “Purchase,” “Add to cart,” etc. 
3. Expand any category by clicking on the downward-facing arrow icon next to the “Edit goal” button. 

4. Select any conversion action for which you want to change the Google Ads attribution model and click on its blue name. 
5. You will see its details, settings, and webpages. 
6. Click on settings, and scroll down to attribution.

7. Select the appropriate attribution model and save your changes. 

What are Creditable Channels in Google Ads? 

Creditable channels are the channels that are eligible to receive a credit for a conversion in your Google Ads account. 

Currently, your account can include conversions from the following channels: 

1. Google paid channels (Google Ads channels)
2. Paid channels 
3. Paid and organic channels
4. [Publisher] channels
5. Unknown channels 

💡If you have set up conversions across multiple Google products, the channels that receive credit may vary based on how activity is measured across each platform.  You can easily find which channels get credit for your conversions next to the “Attribution Model” setting in Google Ads, Google Analytics, Search Ads 360, Display & Video 360, and Campaign Manager.

Google Ads Attribution Reports 

Google Ads attribution reports help you understand the paths that your customers take to complete a conversion. They share granular insights into how your various advertising efforts work together to drive conversions for your business. 

Through these reports, you can check whether any specific keywords assisted a particular conversion that occurred through other keywords. This gives you more clarity and a better sense of your customers’ conversion path, rather than just knowing which was the last-clicked keyword. 

Where to Find Attribution Reports in Google Ads? 

To find the attributions report: 

1. Go to “Goals” from the left side menu in your Google Ads account. 
2. Click on the “Measurements” drop-down. 

3. Click on “Attribution.” 

Pro tip: If you have an MCC account under which you manage multiple Google Ads accounts, then we recommend using cross-account conversion tracking. Once that is set up, use the attribution reports in your MCC.

How to Use Attribution Report Controls? 

You can also use certain controls that enable you to customize your attribution reports. These include: 

1. Date Range: Primarily helps to determine which conversions will appear in the report. 
2. Dimension: Used to change how Google groups your data. You can view performance by Campaign, Ad group, Keyword, or Device. 
3. Conversion Action: Use this filter to select specific conversion actions. By default, reports include primary conversion actions. 
4. Lookback Window: The lookback window specifies from how far back ad interactions were taken into consideration for attribution before a conversion occurred. You can select from 30, 60, or 90 days.

Different Types of Attribution Reports 

You can access different types of attribution reports, such as: 

1. “Overview” Report: Gives a high-level summary of your conversion paths. It also provides information on how many days and ad interactions users needed before converting, cross-device activity, and which campaigns assisted conversions most often. 
2. Conversion Paths Report: The “Conversion paths” report shows the most common paths that your customers take to complete conversions. It provides this information based on the ads that your customers clicked on before a conversion is recorded. You can refine this report further using “View Menu,” “Devices Dimension,” etc. 
3. Path Metrics Report: This report shows how long and how many interactions in total it takes for users to convert. Through this report, you can also analyze how many conversions happened after a given number of days or interactions, and what the value of those conversions is. 
4. Model Comparison Report: It lets you compare two different attribution models side by side. We recommend jumping on to the next section, where we discuss these reports a bit more in detail. 

Note: Conversion data may differ between the Attribution reports and the “Campaigns” page.  This is primarily because both sections count conversions in a different manner. Attribution reports count conversions by conversion time and also include lookback window adjustments. Whereas the “Campaigns” page counts conversions by ad interaction time and follows the defined conversion window.  Use Attribution reports to understand how the Google Attribution model affects reporting. Use the “Campaigns” page reports to optimize performance after you select your desired attribution model.

What are “Model comparison” Reports? 

The “Model comparison” report in Google Ads enables you to compare two Google Ads attribution models side by side. It helps you understand how conversion credit changes under different models. 

For example, you can compare Last Click with Data-driven attribution. Through that comparison, you can identify keywords, devices, or campaigns that may not have received the credit they deserve under the Last click model. 

Pro tip: When you use the “Model comparison” report, we recommend checking both the “Cost/conv.” and “Conv. value/cost” columns. That will allow you to compare the CPA and RoAS for both attribution models.  If a campaign shows a higher RoAS and lower CPA under the Data-driven model, then it would be fair to conclude that it may be contributing more across the full conversion path than the last click model suggests. And thus, you can go ahead and adjust bids on the true impact it created rather than relying on last click performance.

Google Ads Attribution Models vs Google Analytics Attribution Models

Let’s also understand the differences in attribution across both Google Ads and Google Analytics. 

Aspect	Google Ads	Google Analytics 4
Attribution model options today	– Data-driven  – Last click only	Data-driven Paid and organic last click Google paid channels last click
Where can you set it	At the conversion action level	Includes property-level attribution settings for key event reports
Does a model change rewrite history?	Applies going forward for conversion counts. “Current model” columns simulate historical impact.	Applies to historical and future data for event-scoped traffic dimensions.
Default lookback/window	Most reports show a 30-day lookback window by default when you open them	30-day default event lookback window for acquisition conversion events and 90-day for non-acquisition conversion events
Channel scope	It is mostly centered on Google Ads touchpoints and eligible interactions	Includes reports from paid and organic channels, depending on the settings you configure
Why conversion count differ	Conversion count differs due to different windows, modeling approaches, etc.	Different windows and channel scopes. GA4 also uses its own attribution settings and definitions.

Conclusion and Takeaways: Which Google Ads Attribution Model Should You Choose? 

In terms of which Google attribution model you should choose for your business, there is no one-size-fits-all answer.

Brands like Mercedes-Benz (in Germany) have run six-week experiments with campaigns that use data-driven attribution with ‘Maximize conversions’ bidding strategy, and noticed a 37% increase in conversions. This shows how distributing credit across the full conversion path can unlock better performance. 

So, if you run multiple types of ad campaigns (Shopping, Search, etc.) for your brand, you can use a data-driven attribution model, which Google also recommends. 

However, if you run a small business with short buying cycles and limited data, Last click may still work well. It keeps reporting simple and requires less volume for stable results.

Key takeaways from this blog include: 

• Google Ads currently supports only ‘Data-driven’ and ‘Last click’ attribution models. Older rule-based models like ‘First Click,’ ‘Linear,’ ‘Time decay,’ and ‘Position-based’ are no longer supported.
• Data-driven attribution uses your account’s real conversion data to distribute credit across multiple touchpoints. It works best when you have strong conversion volume and complex multi-touch journeys.
• Last click attribution assigns full credit to the final interaction before conversion. It is better suited for simple funnels with short sales cycles and limited data.
• Attribution models directly impact how conversions are counted in the “Conversions” column. This means they also influence Smart Bidding strategies like Target CPA and Target ROAS.
• Changing your attribution model can shift conversion credit across campaigns and keywords. As a result, CPA and ROAS may change even if actual performance stays the same.
• Attribution reports and the Model comparison report help you analyze assisted conversions and compare models before making a switch.
• Always align your attribution model with your business goals, buying cycle length, and available data volume.

Good luck! 

Also read: Ad Group in Google Ads  Google Ads Conversion Rate Setting Up Google Ads Conversion Tracking On Shopify

FAQs

1. How many attribution models does Google have?

Currently, Google has 2 attribution models: Data-driven and last click. 

2. What is a 7-day click 1-day view attribution?

It essentially captures those users who show immediate interest (1-day view) and those who take action (such as completing a purchase, signing up, etc.) after a consideration period (7 days). 

3. Why are my conversions not recording or showing as “Inactive” after changing the attribution model? 

If conversions stop recording or show an “inactive” status, the issue is usually related to your tracking setup and not the attribution model you switched to. 

To resolve it, ensure that your Google tag is implemented properly across all pages (such as thank you or confirmation pages). Additionally, use Google Tag Assistant to test your setup. 

If you use Google Tag Manager, ensure that the Conversion Linker Tag is active. 

On top of everything, perform test conversions, as that can also help. 

4. What are the requirements for using Data-driven attribution? 

All conversion actions in Google Ads are eligible for data-driven attribution. There is no strict minimum required to activate it. 

However, for effective attribution, Google recommends that you have at least 200 conversions and 2,000 ad interactions within a 30-day period across all supported networks. 

This is to ensure that the model can identify patterns more accurately and assign credit more precisely. If your conversion volume is low, the data-driven attribution model will still but you might not get the best results. 

5. What is cross-network attribution? 

Cross-network attribution enables you to understand how your advertising efforts across different Google networks (such as Search, YouTube, and Display) work in tandem to drive conversions.