Updated for 2025: A Practical Guide to Cross-Channel Digital Attribution
Heading into 2025, we’ve updated this guide, created in partnership with ISBA, to help you get a head start in developing a strong framework for measuring cross-channel attribution in your digital advertising.
Why is it important to measure the performance of advertising?
The persisting economic uncertainty which characterised 2024 is expected to shape business decisions well into 2025, leading to continued scrutiny on budgets and reluctance to spend on advertising. It remains critical to get a true view on the performance of advertising – that is, a holistic view of the incremental impact of advertising to the bottom line. This includes leveraging emerging tools and trends like AI-driven attribution models, and faster, less expensive marketing mix modelling (MMM) studies, which have become more prevalent through 2024 and into 2025. Only then are we fully accountable and we can make genuinely informed decisions, seizing opportunities for growth despite ongoing uncertainty and adapting to potential market shifts in 2025.
Why is it difficult to measure the performance of digital advertising?
Given the amount of data and the number of metrics associated with digital advertising, it’s not unreasonable to assume that the measurement of performance is straightforward. However, the reality is somewhat different; measurement of the performance of digital advertising is rather challenging.
We are operating in a complex marketing environment that is characterised by a multitude of obstacles. Three key issues that are continuing to make measuring digital advertising effectively more challenging are:
- An ever-expanding array of media channels and touch points
- The walled gardens between platforms
- The rise of consumer privacy concerns
That is alongside continued concerns about data consistency and usability from the sunsetting of Google’s Universal Analytics in 2023.
1. An increasingly fragmented media landscape and complex user journeys
The proliferation of digital platforms and lower barriers to entry for advertisers have led to increasingly fragmented media mixes. This is exacerbated by the need for businesses to establish a presence on a wider range of platforms to reach target audiences effectively. As consumers’ journeys have become more intricate, involving multiple touchpoints across a multitude of channels, the accurate attribution of conversions has naturally become a more complex task.
The growing investment in retail media and CTV, combined with the rising popularity of emerging social platforms like Threads and Bluesky, suggests that this fragmentation will continue to accelerate.
2. Walled gardens between platforms
Walled gardens – or isolated ecosystems within digital platforms – have further complicated the measurement landscape. These gardens, such as Meta, Google, and Amazon, keep user data within their walls, making it very difficult to track complex user journeys and assess the overall effectiveness of cross-channel marketing efforts. Whilst the platforms offer solutions to optimise and fine-tune on-platform activity, there are potentially severe limitations regarding the measurement of the true incremental impact; many advertisers can double/triple-count sales or leads, if users have crossed between platforms in their journeys.
3. Increase in privacy concerns: iOS and degraded third-party cookies
Concerns around privacy will remain a key focus in 2025. Apple’s recent updates, including iOS 18, continue to introduce more privacy-centric features, further limiting the ability to track user behaviour across apps and websites.
Additionally, Google’s decision to retain third-party cookies in Chrome, while providing users with the choice to allow them, signifies a shift towards increased user control over data privacy. In addition, over 1/3 of UK browser users already use Safari and Firefox which block cookies by default (Statista).
These developments continue to cause severe restrictions on traditional tracking methods, forcing marketers to adapt to a new era of privacy-first strategies.
How can you measure the results of your digital advertising?
In this dynamic digital landscape, it is essential for marketers to adapt and evolve their measurement strategies. Embracing uncertainty and making measurement a part of the cultural fabric of marketing teams is crucial to success, and whilst measuring the true impact of your efforts has become increasingly challenging, it isn’t a lost cause. A good measurement strategy needs to evaluate digital advertising alongside the rest of the media plan and it requires some key steps:
1. Define a clear vision of success.
Measurement should support decision making, it should support those responsible for the decisions being taken. Identify which decisions should be informed and by whom, how measurement translates into action and understand when the decisions need to be taken (for example, annual budget setting vs. weekly in-flight optimisation).
2. Bring the right people around the table.
Key stakeholders from across the business should be brought together to validate the vision of success and identify barriers to adoption/change. A successful measurement strategy brings people together and provides collective learning, when previously they behaved separately.
3. Develop a measurement and testing framework, recognising there is no single source of truth
The framework should align to decision making and link KPIs across the consumer journey to a common growth metric. Recognising that there is no single source of truth in digital attribution due to its complexity and the external factors at play, the framework should map the best measurement approach/solution to specific decisions. The framework should allow you to monitor performance through the entire customer journey, from initial awareness to conversion, enabling you to demonstrate progress accurately.
4. Leverage complementary measurement approaches for a holistic view
To gain a complete understanding of marketing effectiveness, combine in-platform testing, Multi-Touch Attribution (MTA) solutions, and Marketing Mix Modelling (MMM). Each approach provides unique insights:
- In-platform testing offers granular campaign-level learnings and helps you understand how specific ads, campaigns, and audiences perform. Whilst it’s important to remain sceptical about overall conversion data within each platform, you should still leverage platform data.
- Multi-Touch Attribution (MTA) connects multiple touchpoints across the customer journey to give a more accurate picture of which interactions drive conversions. Key here is researching MTA platforms to find one that you’re confident in the methodology being used (particularly with any claims of AI), that is suited to your specific mix of digital channels.
- Marketing Mix Modelling (MMM) delivers a macro-level view, accounting for both online and offline channels as well as external factors like market conditions. MMM does not require any digital tracking, making it impervious to issues relating to cookies and privacy, and is able to de-duplicate revenue across different channels in a way that the walled gardens of platforms are not able to. In-platform and MTA data can then be used to calibrate the findings from MMM and optimise on a more regular basis between MMM studies.
You can find out more about MMM here.
By using these approaches together, you balance short-term performance insights with a long-term understanding of marketing’s incremental impact. This layered approach ensures that your measurement strategy is both robust and adaptable to evolving business needs.
5. Embed the learning, ensure action.
Your measurement strategy needs to have senior endorsement and a plan to provide wider awareness and education across the business. It’s especially important to articulate the value-add to both the business and the role of individuals. Workshops and demonstrations – supported by tools/dashboards – can be invaluable when seeking to embed measurement across the planning cycle. Further, personal performance measures should be aligned to any changes you make.
Summary
In conclusion, measuring digital advertising in 2025 will remain no easy feat, given the evolving privacy and technological landscape. Marketers must adapt and embrace data-informed decision-making and employ a mix of processes and tools. This includes measurement frameworks, Marketing Mix Modelling, and platform data analysis. By doing so, marketers can gain a more accurate understanding of the performance of their media mix and navigate effectively the challenges posed by the digital marketing landscape.
At Entropy, we support advertisers with both Dynamic Marketing Mix Modelling (DMMM) and hand-crafted MMM. A DMMM analysis quickly pays for itself as you optimise your media mix based on the findings. Find out more about our MMM modelling measurement services.
If you need any help with setting up, running or measuring your digital marketing, get in touch with Entropy and we’d be glad to help.
