Marketing Attribution Models: Which One Should You Use?

Why Attribution Models Matter

Attribution models determine how credit for a conversion is distributed across the marketing touchpoints that preceded it. The model you use changes which channels appear to be working — and therefore changes where you invest your next marketing budget. A company using last-click attribution will systematically over-invest in bottom-funnel channels (branded search, remarketing) and under-invest in top-funnel channels (content, display, YouTube) because last-click ignores everything that happened before the final click.

The Main Attribution Models

• Last-touch: 100% credit to the final touchpoint before conversion. Simple to implement, but undervalues awareness and consideration channels. The default in most platforms historically.
• First-touch: 100% credit to the first touchpoint. Useful for understanding which channels initiate customer relationships, but ignores the entire conversion process.
• Linear: Equal credit across all touchpoints in the journey. More balanced but doesn't reflect that different touchpoints have different impacts.
• Time-decay: More credit to touchpoints closer to conversion. Reasonable assumption for short sales cycles, but over-rewards last-minute remarketing.
• Position-based: 40% to first, 40% to last, 20% shared across middle. Recognises both initiation and conversion touchpoints.
• Data-driven (GA4 / Google Ads): Machine learning assigns credit based on patterns in your own conversion data. More accurate than rule-based models when you have sufficient conversion volume (typically 300+ conversions per month).

Practical Model Selection

For most businesses: use data-driven attribution in GA4 and Google Ads if you have sufficient volume. If you don't, use time-decay or position-based (both better than last-click for balanced budget decisions). Always combine digital attribution with periodic incrementality testing to validate that attributed channels are actually generating incremental revenue.

Attribution Across Platforms

Attribution gets more complex when comparing across platforms — each uses its own model and conversion window. Our marketing analytics consulting uses BigQuery to build a unified attribution model across all channels, giving you one consistent view instead of three conflicting platform reports. Contact us to design your attribution framework.