When it comes to cosmetics, safety and quality are non-negotiable. To guarantee that every product reaching consumers maintains its integrity from production to the end of its shelf life, the stability and compatibility test plays a vital role. At CE.way, we support cosmetic companies worldwide in performing these tests in line with EU and UK regulations, helping brands ensure product performance, safety, and compliance.
Why Stability Testing Matters
Under EU Cosmetics Regulation 1223/2009 and the UK Product Safety and Metrology Regulations 2019, stability testing is a mandatory requirement, forming a core part of the Cosmetic Product Safety Report (CPSR).
The main goals of stability testing are to:
- Determine whether the product maintains physical, chemical, and microbiological quality over time.
- Assess safety and functionality throughout storage, transportation, and consumer use.
- Define the product’s shelf life or period after opening (PAO).
This ensures that every cosmetic sold on the market continues to meet consumer expectations in terms of safety, aesthetics, and effectiveness.
Compatibility With Packaging
The choice of packaging is just as critical as the formula itself. Stability and compatibility testing evaluates:
- How well the packaging protects the product from external factors.
- Whether substances from the packaging could leach into the cosmetic, potentially affecting safety or quality.
To guarantee reliable results, every formula–packaging combination must undergo compatibility testing. Furthermore, stability and compatibility tests must be repeated whenever there is a change in formula, packaging, or manufacturing process.
Types of Stability Testing
At CE.way, we offer both real-time and accelerated stability tests:
- Real-time stability tests simulate actual storage conditions at room temperature and typically run for the full intended shelf life.
- Accelerated stability tests expose products to elevated temperatures (37–45°C) over three months, providing faster insights into long-term stability.
We also provide additional testing methods, such as:
- Refrigeration and freeze-thaw cycles to predict transport resilience.
- Sunlight exposure tests for transparent packaging.
Our procedures follow ISO 18811:2018 standards, ensuring globally recognized quality and reliability.
What We Monitor
During stability and compatibility tests, our team carefully evaluates:
- Physical and chemical specifications (pH, viscosity, density)
- Microbiological properties
- Organoleptic characteristics (appearance, smell, texture)
- Packaging compatibility and its interaction with the product
These parameters help predict how the cosmetic will behave under real-life conditions, ensuring both compliance and customer satisfaction.
CE.way – Your Trusted Regulatory Partner
Choosing the right stability test depends on the type of cosmetic and the desired shelf life. At CE.way, we provide tailored guidance to help you select the most suitable testing method. Our experts not only perform the required tests but also integrate the results into your Product Information File (PIF), making compliance seamless.
Pharmaplast, one of our international partners, shared their experience:
“CE.way is our cosmetics consultant who looks after compilation of PIF, safety assessments and CPNP notifications. In addition to this, CE.way is our European representative. Their professionalism and expertise make compliance simple and reliable.”
Secure Your Market Entry With Confidence
With CE.way, cosmetic brands can ensure that their products are safe, compliant, and market-ready. From stability and compatibility testing to full regulatory support, our services are designed to simplify complex processes and give you peace of mind.
👉 Get in touch with CE.way today to learn how we can help you meet EU and UK requirements while guaranteeing the highest standards of product safety and quality.
