Tealium vs. Google Tag Manager: A Security-Focused Comparison

This article is a follow‑up to the comparison we previously did between Adobe Tags and Google Tag Manager. As promised at the end of that post, this time we look at how Google Tag Manager (GTM) stacks up against Tealium, from a privacy and security perspective. But first, a quick refresher:

What Tag Managers Are

Tag managers help organisations deploy and control small pieces of code called tags on their websites, mobile apps, or digital platforms. These tags power essential business functions, like:

• Web analytics (e.g., Google Analytics, Adobe Analytics)
• Marketing pixels and conversion tracking
• A/B testing and personalisation tools
• Consent and privacy scripts
• Heatmaps, session replay, and performance monitoring
• Fraud detection and security monitoring

Traditionally, adding or updating tags required developers to modify site code. But tag managers solve this by giving teams a central interface where they can manage all their tags safely and efficiently, without the need to make code changes every time.

The Market

Google Tag Manager is the biggest player in this field. According to a survey on https://w3techs.com, GTM had a 99.7% share of the market in 2023, while Adobe DTM and Tealium only accounted for 0.4% and 0.2% respectively. GTM has slipped to 94.04% more recently, according to some sources, but it remains the dominant player.

This might give you pause to ponder: why bother comparing GTM with other tools when it’s so dominant?

Well, the headline figures don’t tell the full story. GTM may be the big dog in the market as a whole, but it doesn’t suit every use case. Its standard web tracking tier may be free, widely supported, and well-integrated into the Google ecosystem that’s familiar to so many users, but it doesn’t always suit the needs of enterprise customers with complex governance requirements.

Larger customers in regulated markets like health, finance, and international e-commerce must navigate challenging security and privacy standards. While GTM is capable of fulfilling their governance, privacy, and security requirements, it can only achieve this when it’s configured correctly. Customers need to weigh up whether it’s worth putting in the time and resources needed to achieve this when they could pay for a dedicated enterprise-grade solution that meets their needs out of the box.

Tealium is enterprise-grade, and it powers complex, multi-channel deployments for large organizations with over 1,300 turnkey integrations and advanced data governance.

GTM may be simple and cheap, but Tealium offers vendor-agnostic flexibility, real-time data control, and built-in privacy tools, so it’s well worth doing a side-by-side comparison.

Vendor Agnostic

This term is worth a quick explanation. Vendor-agnostic means Tealium is not tied to any specific marketing, analytics, or advertising ecosystem, and that’s important. The likes of Adobe Launch or Google Tag Manager are strongly connected to their respective ecosystems, but Tealium will get along famously with almost anybody else’s.

You can connect it to Adobe Analytics, Google Analytics, Meta / TikTok / LinkedIn, Salesforce, HubSpot, Snowflake, AWS / GCP / Azure, or any custom endpoint without the need to optimise it for any single vendor’s tools, and without being ‘pushed’ towards any particular one.

This is a big contrast to:

GTM → Optimized for Google Marketing Platform

Adobe Launch → Optimized for Adobe Experience Cloud

Core Features and Functionalities: Tealium vs Google Tag Manager

Both platforms allow non-developers to manage tags, but each takes its own approach:

• Terminology and Concepts: GTM uses “Containers” (for sites/apps), “Variables” (data elements), and separate “Tags” + “Triggers”. Tealium employs “Profiles” (similar to containers), a robust “Data Layer” with advanced enrichment, “Tags” from a massive marketplace, and “Load Rules” for firing conditions.
• User Interface and Ease of Use: GTM’s interface is intuitive and beginner-friendly with pre-built templates. Tealium offers a more modular, powerful UI tailored for enterprise teams, although this means it has a steeper learning curve.
• Customization and Integrations: GTM supports custom HTML/JavaScript but requires more manual work. Tealium shines with 1,300+ pre-built tags (vs. GTM’s 100 or so), extensions for data manipulation, and seamless CDP integrations.
• Server-Side Tagging: Both platforms support server-side tagging (GTM via Google Cloud, Tealium via its EventStream), but Tealium provides stronger out-of-the-box omnichannel and consent enforcement.

For simple setups, GTM wins on speed. For complex, scalable implementations, Tealium dominates.

Security Landscape: Data Privacy, Access Controls, and Vulnerabilities

Security is where these platforms diverge sharply.

Google Tag Manager Security Features

• Granular permissions at the account/container level
• Consent Mode for basic privacy compliance
• Tag blocking and preview modes to mitigate misconfigurations
• ISO 27001 certified, with two-factor authentication (2FA)

Tealium Security Features

• Enterprise-grade role-based access control (RBAC), SSO, and audit logs
• Built-in Consent Preferences Manager and integrations with leading CMPs
• Data encryption, access controls, and compliance tools for GDPR/CCPA
• Fewer custom scripts are needed due to extensive pre-built tags, reducing injection risks

User Access Control

GTM offers solid container-level controls but lacks Tealium’s fine-grained, enterprise Role-Based Access Controls and dedicated support for compliance audits.

Security Risks with GTM Misconfigurations

GTM’s open nature allows arbitrary custom JavaScript,which creates a large attack surface. Common issues include:

• Malicious tags injecting scripts (e-skimming attacks have been reported)
• Data layer leaks exposing personal identifying information
• Third-party tags bypassing permissions or loading external code covertly
• Consent gaps if not wired properly

Mitigating Risks in Google Tag Manager

Use workspaces, version control, tag templates (to limit custom code), and third-party tools like Reflectiz for script monitoring. Server-side GTM can help here, but it requires expertise.

Tealium Security-by-Design Principles

Tealium emphasizes “trusted data” with pre-vetted tags, automatic consent enforcement per category, and reduced reliance on custom code. Its modular architecture minimizes vulnerabilities, and its built-in privacy tools prevent unauthorized data flow.

Data Residency Considerations: Tealium vs Google Tag Manager

GTM processes data primarily through Google servers (with server-side options for region selection). Tealium offers flexible data routing, real-time streaming, and stronger controls for residency compliance, which makes it ideal for regulated industries.

Security Implications: Open vs. Somewhat Closed Ecosystems

GTM’s fully open ecosystem gives users ultimate flexibility but heightens the risks they can expect from unvetted third-party code. Tealium’s vendor-agnostic but highly integrated marketplace (with pre-built, secure tags) strikes a balance: it’s still flexible yet more controlled, significantly reducing the attack surface for enterprises.

Additional Considerations

• Performance: Both load asynchronously; Tealium often edges out with advanced data layer optimization.
• Cost: GTM is free (enterprise-grade GTM 360 is paid); Tealium is subscription-based (custom pricing).
• Support: GTM relies on community/forums; Tealium provides dedicated enterprise support.
• Best For: GTM for SMBs and Google-heavy stacks; Tealium for large-scale, privacy-focused operations.

GTM 360?

That mention above of GTM 360, the enterprise version of Google Tag Manager, might prompt you to ask why we aren’t comparing like-for-like and wheeling it out for comparison with Tealium.

Well, the truth is, they aren’t exactly the same. GTM 360 is still deeply embedded in the Google ecosystem (Google Analytics / Google Ads / Google Marketing Platform), and many of its strongest value-adds come when you’re already using Google tools.

Tealium still has the advantage of being platform agnostic, but GTM 360 may be worth considering for enterprises that are already heavily invested in the Google ecosystem.

However, if your organisation has:

• Very complex tagging across web, mobile, IoT, apps, and offline, across multiple geographies.
• Strong privacy/regulatory compliance needs (GDPR, CCPA, ePrivacy, etc) and wants advanced vendor governance, consent control, and identity resolution.
• You want to maintain vendor-agnostic flexibility (so you’re not locked into Google).
• You want broader data orchestration (CDP, event stream, audience orchestration) in the same platform

…Tealium is the one to go for.

Conclusion: Choosing the Right TMS with Security in Mind

Neither platform is inherently “insecure,” but risk profiles differ. GTM suits cost-conscious teams willing to invest in best practices and monitoring. Tealium is the enterprise choice for built-in governance, reducing human error and third-party vulnerabilities.

For context, Adobe Experience Platform Tags (AEP Tags/ATM) offers a closed, security-by-design ecosystem, so it’s best for Adobe-centric enterprises needing strict controls.

Who Should Choose What?

• Small-to-medium businesses, basic needs, Google ecosystem: Google Tag Manager
• Enterprises with complex data, strict privacy/compliance: Tealium iQ
• Large organizations invested in Adobe Experience Cloud: Adobe Tags (ATM)

Ultimately, no matter which tag manager you go with, prioritize third-party tag monitoring, consent enforcement, and regular audits.