If you’re running marketing for a B2C business, it’s somewhat of an understatement to say you’ve probably noticed that attribution has become significantly harder over the past few years. Between browser privacy features, regulatory requirements, and rising ad-blocker usage, the tracking landscape we once relied upon has fundamentally changed.
The much-discussed “death of the cookie” didn’t arrive as a single dramatic event. Instead, we’ve witnessed a gradual erosion of data quality that continues to accelerate. In this blog we’ll explore how attribution has evolved over the past few years and whether Multi-Touch Attribution still delivers meaningful value for your marketing decisions.
Several converging forces have made traditional attribution approaches increasingly unreliable. Understanding these challenges is essential before we can explore practical solutions.

Regulatory pressure continues to intensify as well. The Digital Markets Act now places the burden on “gatekeepers” like Google and Meta to ensure explicit consent. This has made tools like Consent Mode v2 a mandatory requirement rather than an optional enhancement.
Crucially, the rise of ad blockers adds another layer of complexity: a substantial percentage of savvy users now use browsers like Brave or extensions that block tracking scripts entirely, creating what we might call “dark matter” in your analytics.
Direct, cookie-based cross-device tracking is effectively dead for unauthenticated users. However, businesses have adapted using three primary methods.

Server-side tracking moves the data collection process from the user’s browser to your own server. This architectural shift offers several meaningful advantages.
data.yourdomain.com), you can set “server-managed” cookies. These can extend your attribution window back to one year, bypassing the seven-day cap imposed on JavaScript-set cookies. For businesses with consideration cycles measured in weeks or months, this difference is substantial.As of 2026, Google Consent Mode v2 is no longer optional for businesses operating in the EEA or UK. It introduces two new signals — ad_user_data and ad_personalization—which dictate whether Google can use data for modelling and remarketing.

When users provide consent, you receive one-to-one data tracking just as before. When they don’t consent, GA4 uses behavioural and conversion modelling. The platform analyses the behaviour of users who did consent and uses machine learning to extrapolate patterns for those who didn’t. To implement this correctly, you must use a Google-certified Consent Management Platform to communicate these signals.
When users don’t consent to being tracked, you still receive records of page views and other ecommerce and other user activity events in your GA4 or Segment data exports, you just can’t attribute them to a specific user or session. This does mean you can still measure the popularity of an article or product on your site, but you can’t connect that activity-together to understand the path to conversion.
While GA4 handles modelling as a “black box,” Snowplow (and the open-source OpenSnowCat fork from our partners at SnowCatCloud) provides a warehouse-first approach that many data-mature organisations find compelling.
With Snowplow and OpenSnowCat, you gain raw data ownership: granular, un-sampled event data delivered directly into your warehouse — whether that’s Snowflake, BigQuery, or another platform. You’re not constrained by Google’s attribution logic, which means you can build custom models using techniques like Markov Chain analysis with 100% of your first-party data.
Snowplow also offers privacy by design. You maintain complete control over what’s collected, making it easier to comply with specific regional requirements. For organisations with sophisticated analytics capabilities, this flexibility can be transformative.
When data loss reaches 40–60%, traditional MTA becomes unreliable. The industry has responded by adopting a triangulation approach that combines multiple methodologies.
We’ve actually built two open-source attribution packages over the past few years and it’s useful to look-back at them to understand what’s still relevant in those packages, what is no longer relevant and how they can be updated and extended to go beyond basic multi-touch attribution.
The first, ra_attribution, is a dbt package for multi-cycle, multi-touch revenue attribution that was released four years ago when MTA was the undisputed standard.

It handles the full complexity of attributing account openings, first orders, and repeat purchases; sourced data from Snowplow, Segment, or Rudderstack and supporting everything from First Click to Time-Decay models.
The second, ra_attribution_for_ga4, came about when Google removed rules-based attribution from GA4 entirely in 2023, forcing everyone onto their “data-driven” model.

A black box attribution model that changes weightings year-on-year makes comparison reporting essentially meaningless as you never know whether increased conversions came from your improved campaigns or Google tweaking the algorithm; this GA4-specific SQL and Looker repo used BigQuery export to give you back first-click, linear, time-decay and time-decay models using logic you control.

This separation remains critical for allocating budget appropriately across acquisition and retention efforts.
2. Identity stitching and blended user IDs have if anything become more important, not less. The package’s use of a blended_user_id based on both visitor IDs and authenticated user IDs is now the modern standard. For B2C retailers where customers often browse on mobile and purchase on desktop, this logic is essential for de-anonymising the customer journey and connecting fragmented touchpoints.

3. The warehouse-first architecture has aged well. Whether you’re using ra_attribution with Snowplow data in Snowflake or ra_attribution_for_ga4 with BigQuery export, sourcing event data directly into your warehouse provides the raw data ownership necessary for deep attribution analysis.
4. And support for diverse attribution models from First Non-Direct Click to Time-Decay remains relevant as a tactical optimisation tool. Different models answer different questions, and having the flexibility to compare them side-by-side helps marketers understand channel contribution from multiple perspectives. The GA4 package in particular was built precisely because Google took this flexibility away.

Several assumptions that were however baked into both packages no longer hold true in 2026’s privacy landscape.
If you’re using either of our attribution packages. or building a similar warehouse-based attribution system then several updates will significantly improve their usefulness in 2026.
data.yourstore.com) will enable you to set server-managed cookies that bypass browser caps and maintain that 30-day attribution window. This single change can dramatically improve data quality for both packages.blended_user_id logic in ra_attribution can deterministically stitch cross-device journeys without relying on probabilistic matching. For GA4 users, authenticated user IDs significantly improve the quality of cross-device reporting.Multi-touch, multi-cycle marketing attribution still remains relevant in 2026, but it can no longer serve as your single source of truth. B2C retailers we’re working with today are treating MTA as one input among several: MTA for tactical optimisation, MMM for strategic allocation, and incrementality testing for causal validation.
Rittman Analytics is a boutique data analytics consultancy that helps ambitious, digital-native businesses scale-up their approach to data, analytics and generative AI.
We’re authorised delivery partners for Google Cloud along with Oracle, Segment, Cube, Dagster, Preset, dbt Labs and Fivetran and are experts at helping you design an analytics solution that’s right for your organisation’s needs, use-cases and budget and working with you and your data team to successfully implement it.
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