How to maximize ROAS without third-party cookies

Digital advertising is an essential way to reach customers across their many online channels — but evolving privacy regulations have made tracking and targeting audiences harder than ever.

Marketers and advertisers need to make calculated bets on who to target, where to reach them, and how to approach them. And they need a consistent (and accurate!) way to see if their investments are paying off.

Return on ad spend (ROAS) is a popular way to measure how effective a marketing team is with its advertising. Simply, ROAS measures the results of advertising, either holistically or on a campaign or platform basis. ROAS does not factor in every cost 
to execute your advertising — like infrastructure or platform costs — which are reflected in your return on investment (ROI).

85% of marketing leaders are concerned about the impact of privacy regulations, with 40% facing new challenges with generating leads and demonstrating ROI.

Privacy regulations have amplified the many hurdles teams face when optimizing 
their ROAS:

• Conversion tracking - Can you tell if someone you target with an ad makes 
a purchase? What if they see the ad but make a purchase several days later?

• Personalization and targeting - Do you understand the specific individuals 
you are actually targeting? Are you able to deliver tailored ads?

• Channel measurement - Are you confident that you know which channels 
deliver the highest return for ad campaigns?

And of course, there’s a major hurdle that has been looming over the advertising landscape for years: the imminent death of the third party cookie.

Download the ROAS guide from GrowthLoop + MetaRouter

The cookiepocalypse

For decades, advertisers and marketers have relied on third party cookies to understand their online audiences and track individual user behavior across sites.

Cookies are small amounts of data stored in a user’s web browser. There are a few different ways cookies behave and originate:

• Session cookies are temporary and get deleted once the user ends their browsing session.

• Persistent cookies stick around after a session 
ends. Persistent cookies do things 
like remember login details 
or website preferences.

• First-party cookies are set by a website the user visits. First-party cookies also remember user preferences, as well as things like pages visited and items added (or abandoned) in a shopping cart.

• Third-party cookies are set by domains other than 
the website the user visits (typically advertisers or analytics services). 
These cookies track user behavior across different websites and have faced scrutiny in recent years.

Most cookies last only a week or two, making it 
hard for marketers to identify users and connect their 
on-site behavior over time. This leads to fragmented 
and redundant visitor profiles and wasted ad spend.  MetaRouter enables companies to connect anonymous users across domains through a persistent first-party identifier enriched with behavioral data that lasts for 
9-12 months.

An issue is that users aren’t so comfortable being tracked. 81% of Americans are concerned about how companies use the data they collect about them, and 67% have little to no understanding of what companies do with the data they collect.

Privacy regulations like the  California Consumer Privacy Act (CCPA) and the European Union General Data Protection Regulation (GDPR) aim to give consumers power back and have led to the phasing out of third party cookies. States including Florida, Montana, Oregon, and Texas introduced new data privacy laws in 2024, and additional state or federal regulations are inevitable.

Given these regulations, Google is removing third party cookies in its Chrome browser — which is the No. 1 internet browser —in 2025, and Firefox and Safari 
also block them.

Without third-party cookies, it’s seemingly harder for marketers to target customers with tailored ads. 41% of marketers expect their biggest challenge to be the inability to track the right data. 44% even predict they’ll need to spend 5-25% more to reach the 
same goals they had set in 2021.

The loss of third party cookies adds to the list of challenges marketers face in optimizing their ROAS:

• Unknown audience information - Organizations will have less actionable customer data from digital sources, especially if they lack reliable 
first-party data.

• ROAS measurement mysteries - Marketers are unable to measure ad-buy effectiveness against view-through behavior if they cannot track users across the sites they visit. This also means teams cannot tie ad-buy effectiveness to subsequent user journeys and respective activities.

• Campaign inefficiencies - Without being able to tie together pre-identify and post-identify journeys — and without reliable view-through behavior attribution —   marketers will likely waste ad 
spend by targeting redundant audiences.

• Data silos - Many marketing teams find themselves siloed across various channel-specific tools. This causes fragmented customer data, resulting in a disjointed strategy and experience 
for customers.

• Complex implementations - Organizations can implement a customer data platform to try to make sense of their customer data, however, 
some CDPs come with high data storage costs 
and costly, time-intensive implementations.

Alternative data collection methods

But not all hope is lost. There are other ways to collect audience data in a compliant way — which give your organization even more confidence than when relying on third party cookies — or deliver personalized ads without direct user data:

1. First-party data - First-party data is one of the safest and most valuable data types to collect. Organizations collect first-party data directly and have complete ownership over it. With the right integrations or data sharing partnerships, teams can build robust and actionable profiles with their first party data (we’ll share more on that next). 

2. Real-time behavioral data - Organizations can extract behavioral data in the moment, gleaning insights from users’ actions, preferences, and interactions as they happen. The challenge is that real-time behavioral data may not reflect historic trends, and it can be limited in its scope.

3. Contextual targeting - Contextual targeting delivers ads based on the context of a webpage. The idea is that a user is likely interested in products or services related to the page they are on (someone reading computer reviews is probably interested in buying a new computer, for example). This can be effective, however, it is not a guaranteed way to reach relevant parties.

Download the ROAS guide from GrowthLoop + MetaRouter

Who are MetaRouter and GrowthLoop?

Marketers often know they could be doing better with collecting and activating customer data, but they don’t know how to — or which solutions might help on their journey. 

This is where MetaRouter and GrowthLoop shine. 

MetaRouter enables organizations to enhance their data collection, tracking, and routing capabilities through server-side tag replacement. This mitigates the drawbacks of client-side tracking, which include privacy concerns, performance issues, and data accuracy challenges. MetaRouter revolutionizes your data analytics strategy including accurate attribution empowering you to make informed decisions and unlock the full potential of your digital presence. 

Better audience targeting starts with having better data. So how does MetaRouter improve your data and ROAS strategy? The solution replaces all your third-party event collection tags and routes events through a single first-party server-side endpoint. Where MetaRouter differs is in its ability to surface a robust ID graph comprised of those tracking identifiers used to provide click-through AND view-through attribution against your impressions and conversions. Not only do you get the benefits of increased signal density through resilience to browser restrictions against third-party code and endpoints, you also maintain measurement parity with traditional data collection means, and a control plane to enforce data formatting and consent-based syndication.

GrowthLoop is a Composable customer data platform (CDP) that empowers marketers to build segments in a unified audience layer, orchestrate journeys across channels, and measure results directly on their Data Cloud. The solution collapses the gap between insights and campaign execution, providing the agility needed to deliver intelligent, personalized customer journeys that transform businesses. By giving marketers the power to wield their company's insights and deliver campaigns faster, they’re able to try more, test more, and win more.

GrowthLoop activates your data and enables you to expand your opportunities for propensity models and predictions. The solution can create distinct customer segments and allow you to target them effortlessly, improving your campaign efficiency, ROAS, and customer lifetime value (CLTV). 

GrowthLoop’s solution has helped organizations across industries – including retail, sports, media, and entertainment, finserv, healthcare, and more – improve their revenue retention, and winback lifts, conversion growth, and marketing campaign velocity. 

Five-step guide to maximizing ROAS with MetaRouter and GrowthLoop

Using MetaRouter with GrowthLoop enables you to collect more customer data by overcoming browser restrictions, enrich your first-party data — stored in GrowthLoop’s composable CDP — and execute targeted ad campaigns with better ease, accuracy, and precision.

All it takes is the following five steps:‍

Step 1: Define a clear objective and KPIs

Define your ad campaign objectives, whether it’s to drive website traffic, increase sales, or raise brand awareness. Establish key performance indicators (KPIs) that align with your objectives, such as conversion rates, click-through rates, or revenue generated.

Step 2: Collect and identify data

It’s more difficult than ever to analyze anonymous and unknown user behavior — but this is one of MetaRouter’s key strengths. Using GrowthLoop with MetaRouter empowers you to collect anonymous user data and analyze it against ad spend, content, and personalization tactics. This allows companies to expand their reach by increasing addressable audiences, and analyze the entire visitor journey for more effective strategies to influence behaviors. ‍

Step 3: Build rich profiles and target the right audiences

MetaRouter merges and captures event data associated with your digital properties, and GrowthLoop identifies signals from additional tool sets within your organization. This provides you with a more complete, 360-degree view of each customer profile for analysis and activation. The rich user profiles allow you to conduct detailed segmentation, build robust audiences, and engage in effective cross-channel activation tactics that influence engagement and conversions. ‍

Step 4: Personalize, analyze, and activate

Ad decisions are more effective when your data is consistent across partners, and you have confidence in your user identities. GrowthLoop activates your customer information into campaigns executed on the best-in-breed tools you have in your martech stack. GrowthLoop’s flexible composable architecture means you can use whatever tools you want and deliver personalized experiences wherever your customers spend their time. GrowthLoop’s generative marketing platform allows you to build highly tailored cross-channel journeys for acquisition, upsell, cross-sell, and churn winback effortlessly. ‍

Step 5: Measure & optimize

By analyzing your ad results for incoming traffic patterns, event metadata, and threat threshold analysis, MetaRouter reduces the amount of traffic from bots or other programmatic “attacks” that skew your analytics and ad spend utilization. This empowers you to more effectively leverage critical customer data for all manner of business decisioning. And using GrowthLoop’s platform, you can measure the success of your campaigns and make changes in real time to optimize performance.

Four benefits of using MetaRouter with GrowthLoop

Your ability to maximize your ROAS is super-powered thanks to these benefits of using MetaRouter with GrowthLoop.   

Increase signal density

Signals are lost to ad blockers, intelligent tracking prevention restrictions, and more. MetaRouter is impervious to these limitations while still allowing for data privacy protections associated with user consent in line with GDPR and CCPA. Re-claim up to 40% of visitor event stream data for better analysis of ad spend efficacy on engagement and conversions.

Surface tracking identifiers

MetaRouter’s identity sync surfaces both click-through and view-through tracking identifiers to the event stream. This allows GrowthLoop to correctly associate engagement and conversion activities to the correct campaign allowing for more effective ad placements.

Link cross-site user journeys

MetaRouter’s cross-site tracking capability allows GrowthLoop to associate cross-site event streams for anonymous and known users to a singular profile. This allows GrowthLoop to analyze and offer decision-making insight around ad-spend effectiveness on cross-site journey behavior.

Track users across sessions

MetaRouter’s first-party identifier for a visitor provides a longer window of time to analyze user behavior compared to third party cookie based identifiers. This allows GrowthLoop to bind a far longer anonymous event stream to a profile and analyze journey behavior influenced by advertisements more effectively.

Example Use Cases

Using GrowthLoop with MetaRouter helps marketers and advertisers enhance their anonymous traffic data and manage their end-to-end data collection, integration, and activation. The solutions empower you to:

• Ensure minimal loss in user tracking attribution against those visitors who do not self identify within owned digital properties.

• Run targeted display, video, CTV, audio, and other types of advertising campaigns

• Launch on-site personalization efforts

• Produce better audiences for single- and cross-channel campaigns 

• Preserve your user tracking attribution against those visitors who do not self identify

• Create retargeting campaigns specific to property visitors who do not self-identify, and meet specific behavioral requirements gleaned from captured event streams.

Staying ahead in a cookieless future

The deprecation of third party cookies is forcing teams to rework their data strategy, and it presents an opportunity to activate a first-party data strategy that maximizes ROAS (and enhances the overall customer experience). 

Organizations can stay resilient by creating a first-party data strategy that captures valuable customer insights at every step of their journey. This data will help deliver tailored messages with precision and show each customer you understand their unique needs and interests. And importantly, you will own all this data, instead of relying on third parties.

Of course, data management is tedious. Customer insights get stale. And it is resource intensive to continually review, update, and merge customer datasets. 

Using MetaRouter with GrowthLoop ensures you are working from clean and accurate datasets with confidence in who you are targeting. The combination makes it effortless to activate your data across the many other martech tools you use — and ensures you make the most of your ad spend! 

Additional Resources

• View-through Attribution (VTA) and Click-through Attribution (CTA) are both critical to understanding the full impact of advertising channels on a prospect or customer–but, they require different data to accurately attribute the impact of the potential customer's decision to act or purchase. Check out how MetaRouter uniquely captures the data necessary for each vendor and passes it to the appropriate one here.

• Staying ahead of the cookieless future requires careful selection of the right platform for activating your customer data. Read GrowthLoop’s guide on how to choose the right customer data solution.

• Explore GrowthLoop University, where you can check out our handy informational articles across a range of topics, including:some textReturn on ad spendIdentity resolutionComposable CDPsFirst-party data platforms

• Return on ad spend

• Identity resolution

• Composable CDPs

• First-party data platforms

Download the ROAS guide from GrowthLoop + MetaRouter