Position-Based Attribution
Position-based attribution is a multi-touch attribution model that gives 40% of the conversion credit to the first touch, 40% to the last touch, and splits the remaining 20% across the middle touches. It is also called U-shaped attribution, because the credit curve dips in the middle and rises at both ends. It exists to reward the two moments that matter most: the touch that found the customer and the touch that closed the sale.
How Position-Based Attribution Works
Position-based attribution assigns fixed weights based on where each touchpoint sits in the journey. The first and last interactions are treated as the most valuable.
- First touch: 40% of the credit
- Last touch: 40% of the credit
- Middle touches: 20% split evenly among them
If a journey has only the middle 20% to share, the math adapts. With two middle touches, each gets 10%. With four middle touches, each gets 5%. A journey with just two touchpoints usually splits 50/50, since there is no middle.
This makes position-based one of the more opinionated multi-touch attribution models. It openly favors discovery and conversion over the nurturing steps in between.
Position-Based Attribution Example
Consider a customer who buys a $500 product after four interactions:
- Clicks a Google Ad (first touch)
- Reads an organic blog post
- Opens a marketing email
- Returns through a direct visit and converts (last touch)
Under the 40-20-40 split, the Google Ad and the direct visit each earn 40%, or $200. The blog and email are the two middle touches. They share the remaining 20%, so each earns 10%, or $50.
Compare that to linear attribution, which would credit each touch 25% and $125. Position-based instead rewards the ad that started the journey and the visit that closed it, while still acknowledging the middle.
When to Use Position-Based Attribution
Position-based attribution suits teams that care equally about generating leads and closing them. It fits a few situations well.
- Funnels where the first and last touch clearly drive results, such as a discovery ad and a final conversion page.
- Balanced budgets that fund both top-of-funnel awareness and bottom-of-funnel closing.
- Lead-gen and demand-gen models, where the introduction and the conversion both deserve real credit.
It is a weak fit when the middle touches do most of the persuading. A long nurture sequence that warms a buyer over months gets only 20% under this model. For those journeys, linear or data-driven attribution gives a fairer split.
Position-Based vs Other Attribution Models
Position-based sits between single-touch models and fully even ones. It picks two favorites instead of one or none.
| Model | Credit split |
|---|---|
| First-click | 100% to the first touch |
| Last-click | 100% to the last touch |
| Linear | Equal share to every touch |
| Time decay | More credit to touches closer to conversion |
| Position-based (U-shaped) | 40% first, 40% last, 20% to the middle |
| Data-driven | Credit by each touch’s measured contribution |
The trade-off is balance versus assumption. Position-based is more realistic than single-touch models because it credits both ends. But the 40-20-40 weights are a fixed rule, not a measured truth, so they may not match how your funnel actually behaves.
Platform Support for Position-Based Attribution
Position-based attribution is no longer selectable in Google’s main tools. Google removed first-click, linear, time-decay, and position-based models from Google Analytics 4 and Google Ads in 2023, leaving only data-driven and last-click. Google stated that data-driven attribution had made the rule-based models redundant.
You can still apply position-based attribution in CRMs, BI dashboards, marketing mix tools, and spreadsheets where you control the weights. Accurate splits depend on clean touchpoint data, which starts with consistent UTM tags on every campaign link so the first and last channels are recorded correctly.
Frequently Asked Questions
What is position-based attribution in simple terms?
Position-based attribution gives 40% of the conversion credit to the first touch, 40% to the last touch, and 20% to everything in between. It rewards the interaction that found the customer and the one that closed the sale. The middle touches share whatever is left.
What is the 40-20-40 attribution model?
The 40-20-40 model is another name for position-based, or U-shaped, attribution. It assigns 40% of the credit to the first touchpoint, 20% to the middle touchpoints combined, and 40% to the last touchpoint. The numbers describe the weight given to each part of the journey.
What is an example of position-based attribution?
If a customer clicks a Google Ad, reads a blog, opens an email, then converts on a direct visit, position-based gives the ad and the direct visit 40% each. The blog and email split the remaining 20%, earning 10% apiece. On a $500 sale, the two end touches get $200 each.
Does GA4 still support position-based attribution?
No, GA4 removed position-based, first-click, linear, and time-decay attribution in 2023. Only data-driven and last-click (cross-channel) models remain selectable. You can still calculate position-based attribution manually or in tools outside Google’s ecosystem.
To choose the right model for your funnel, read linkutm’s campaign attribution guide, which walks through all six models and their trade-offs.