EU Airports Relax Liquid Restrictions After New C3 Scanner Rollout

For nineteen years, a 100-milliliter limit on individual liquid containers governed what European travelers could pack in their carry-on bags. Introduced as an emergency security measure in August 2006, the rule outlasted the specific threat that inspired it, survived multiple technological revolutions in airport screening, and became so embedded in travel culture that millions of passengers now consider miniature toiletry bottles a standard part of packing. That calculus is now changing at airports across the European Union, where new C3 computed tomography security scanners are enabling a quiet but consequential shift in what travelers can bring through security.

As of July 30, 2025, select European airports that have completed their C3 scanner installations allow passengers to carry liquids in containers up to 2 liters in their carry-on baggage, provided total carry-on liquid volume remains reasonable. Laptops and tablets no longer need to be removed from bags at these equipped checkpoints. The changes do not apply uniformly across all European airports; the rollout is tied directly to hardware installation progress, and that progress varies significantly by country, airport operator, and available funding. Travelers who understand which airports qualify and which do not will be far better prepared than those who assume the old rules have simply vanished.

How C3 Scanners Changed the Security Equation

Conventional airport X-ray machines produce two-dimensional images that require trained operators to identify threats based on visual pattern recognition. Liquids and gels were flagged as potential explosive precursors not because the machines could identify specific chemicals, but because they appeared as undifferentiated dense masses that obscured other items and could theoretically conceal explosive compounds. The 100ml limit was a regulatory workaround: by limiting container size, authorities reduced the theoretical explosive yield from any single container to a level deemed operationally manageable.

C3 CT scanners operate on an entirely different principle. Borrowed directly from medical imaging technology, these units rotate an X-ray source around the bag, generating thousands of cross-sectional images that software assembles into a three-dimensional volumetric reconstruction of every item inside. The resulting model allows automated threat-detection algorithms to identify the specific density, atomic composition, and physical structure of individual items, including liquids. The system can distinguish between water, a gel explosive precursor, and a bottle of conditioner with a level of accuracy that conventional X-ray cannot approach.

The consequence is that the 100ml limit, designed to compensate for the limitations of older technology, becomes technically unnecessary at checkpoints equipped with functioning C3 scanners. The scanner can evaluate a full-size bottle of shampoo far more accurately than any checkpoint operator working with a conventional system. Removing the 100ml rule at equipped airports is therefore not a relaxation of security standards but an update to standards that technology has rendered obsolete.

The Rocky Road to Implementation

The EU's C3 rollout did not proceed smoothly. Early deployments at select airports in 2024 initially allowed the expanded liquid allowance, and travelers who flew through those airports in mid-2024 briefly experienced the new freedom. Then, in September 2024, regulators reimposed the 100ml restriction across European airports after a firmware vulnerability in one vendor's scanner software introduced calibration errors that produced unreliable threat-detection readings.

The reimposition was not a reflection of scanner technology's underlying limitations but of the operational complexity of deploying a continental security infrastructure upgrade coordinated across dozens of countries, hundreds of airports, and multiple technology vendors simultaneously. Each scanner installation required independent certification by national aviation security authorities. Each firmware update required validation testing before deployment. When a software defect appeared in early units, the most defensible response for regulators was to return to the known-reliable 100ml baseline while the technical issues were resolved.

By July 2025, the major European hub airports had completed their scanner installations, passed certification requirements, and began full implementation of the relaxed liquid rules. The process had taken nearly two years longer than originally planned, cost significantly more than initial projections, and generated considerable passenger confusion during the period when some airports allowed expanded liquids and others did not. The destination, however, is a genuine and lasting improvement to the travel experience for European flyers.

Which Airports Now Allow 2 Liters

As of mid-2025, the airports that have confirmed full C3 deployment and implementation of the expanded liquid allowance include most major Western European hub airports. Airports in the Netherlands, Germany, France, Spain, and Nordic countries led the rollout, with their larger capital investment budgets and more centralized airport management structures enabling faster deployment. Airports in Eastern and Southern Europe have generally progressed more slowly, with many still operating under the original 100ml framework.

The situation is further complicated by the United Kingdom, which operates its own aviation security framework post-Brexit. UK airports pursued their own C3 rollout independently of the EU process, with several major terminals at Heathrow, Gatwick, and Manchester completing installations on their own schedules. At UK airports with functioning C3 scanners, the liquid rules align broadly with the EU's updated standard, but travelers should verify terminal-specific status before assuming uniformity across an entire airport.

Practical verification before any European journey is essential. Airport operators publish their security screening policies on official websites, and several major European airport authorities maintain updated pages specifically addressing liquid restriction status by terminal. Do not rely on a seatmate's anecdote or a travel blog post from 2024; the status of individual airports has changed multiple times over the past eighteen months, and only current official information is reliable.

How This Changes Packing Strategy

For travelers departing from C3-equipped European airports, the practical packing implications are significant. A standard carry-on bag of 22" × 14" × 9" (56 × 36 × 23 cm), when filled with clothing and personal items, typically has room for a toiletry kit. Under the old 100ml rules, that kit was necessarily limited to miniature containers. At C3-equipped airports, travelers can now pack full-size bottles of shampoo, conditioner, face wash, sunscreen, and similar products, provided the overall liquid volume fits within the bag and does not compromise weight limits.

For travelers on week-long or longer trips, this is more than a convenience. Full-size containers are significantly more economical than travel-size equivalents, easier to find in preferred brands and formulations, and reduce the need to check a bag solely to transport toiletries. A traveler who previously checked luggage primarily because carry-on liquid restrictions made a toiletry-forward packing approach impractical may now find that a well-chosen carry-on handles the entire trip.

The removal of the laptop removal requirement at C3-equipped checkpoints also meaningfully reduces the friction of security lanes. Under the previous system, passengers were required to remove laptops and tablets from bags into separate trays for X-ray scanning, a step that slowed lanes, increased the risk of damage to devices, and created the notorious airport security tray shuffle that cost travelers minutes per screening. At C3-equipped checkpoints, electronics remain in the bag. The scanner's three-dimensional imaging resolves the device's structure and components without requiring physical separation from surrounding items.

The transition to C3 scanning represents the most significant improvement to the European airport security experience since the introduction of automated passport control gates. It has arrived later than expected and rolled out less smoothly than planned. But for the European traveler departing from an equipped airport, the result is a checkpoint experience that is measurably faster, less disruptive, and less reliant on rules designed for technology that ceased to be state-of-the-art a decade ago. That is a meaningful improvement, and one worth understanding before the next departure.