Looking inside RFID labels: the complete guide to their anatomy

More than meets the eye

At first glance, a smart label might appear no different from an ordinary label. It may carry printed branding, a barcode, or product information. Yet hidden within its layers is something far more powerful: a miniature radio device capable of wireless communication, data storage, and real-time tracking.

This ability to integrate intelligence into packaging is what makes smart labelling such a transformative technology. But to design, select, or implement these labels effectively, one must understand their internal anatomy.

Just as a good product cannot succeed without the right packaging, a smart label cannot function without thoughtful construction. Each layer – from the visible facestock to the concealed chip and antenna – plays a role in the performance, durability, and usability of the final label.

In this piece, we will take a detailed look at the structure of a smart RFID label: what it is made of, how it works, and how it can be tailored to different environments. Whether you are a packaging engineer, a purchasing manager, or a brand designer, this insight will help you ensure that your labels do more than stick – they perform.

The physical structure of a RFID label

Smart labels, like traditional self-adhesive labels, are made up of multiple thin layers laminated together. However, they differ in one critical aspect: they contain a functional RFID inlay at their core. This inlay gives the label its intelligence, enabling it to transmit and receive data wirelessly.

Here is a breakdown of a typical smart label structure, from top to bottom:

Face material (facestock)

This is the topmost layer – the one that carries branding, graphics, and printed information. It can be made from paper, polypropylene (PP), polyethylene terephthalate (PET), textured materials, or metallised films. The choice of facestock affects:

• print quality and compatibility
• moisture and UV resistance
• tactile and visual appearance
• sustainability credentials.

Adhesive layer (top side)

A pressure-sensitive adhesive is applied to bond the face material to the RFID inlay or carrier. Adhesive types include:

• permanent or removable acrylics
• hot-melt adhesives for high-speed application
• freezer-grade or high-temperature adhesives for demanding environments.

RFID inlay

The inlay is the most critical part of a smart label. Its design determines:

• read range
• memory capacity
• tag orientation sensitivity
• environmental robustness.

Bottom adhesive (if multilayered)

Some constructions use an additional adhesive layer beneath the inlay – particularly in labels where the inlay is sandwiched between two layers for protection or aesthetic reasons.

Release liner (backing paper)

The final layer is a silicone-coated paper or film liner that carries the label through printing and application machinery. The liner is peeled away during application, leaving the label on the surface.

Release liners are usually made from:

• glassine paper (economical, good die-cutting performance)
• polyethylene-coated kraft (for added strength)
• PET film (for high-speed applications or very thin constructions).

Functional laminate

Together, these layers form a functional laminate – a single structure that must:

• adhere reliably
• remain readable
• protect the chip
• integrate with production machinery
• support printing and branding.

The exact materials and thicknesses used depend on the product, packaging surface, application environment, and RFID system requirements. For example:

• a logistics label for cardboard cartons might use thermal paper with a basic UHF inlay;
• a wine bottle NFC label may feature a metallised paper face, security varnish, and a tamper-evident structure;
• a pharmaceutical RFID label may require low-migration adhesives and full traceability certification.

RFID inlay – the heart of a RFID label

The most important component of any smart label, as was already mentioned, is its RFID inlay – the part that gives the label its digital intelligence. Without it, the label would be no more capable than an ordinary sticker. With it, the label can wirelessly identify itself, transmit data, and trigger real-time interactions across the supply chain and beyond.

An inlay is a thin, preassembled unit that typically consists of three elements:

• Antenna – a metallic structure that captures energy from an RFID reader and transmits the signal.
• Chip – also called the integrated circuit (IC), which stores data and manages communication.
• Substrate – a plastic or paper base that supports the antenna and chip.

These components are bonded together using specialised adhesives and equipment, and the resulting inlay is then integrated into the larger label construction.

RFID antenna design and function

The antenna determines how efficiently a tag can harvest energy from a reader and how far it can transmit data. Its geometry and size depend on:

• the operating frequency (UHF, HF, NFC)
• the desired read range
• the surrounding materials (eg plastic, metal, glass)
• the available space on the label.

Common antenna types include:

• Dipole – two symmetrical branches, common in UHF tags.
• Loop or coil – compact circular or spiral structures, used in HF and NFC.
• Dual-frequency – capable of operating in both UHF and NFC bands for hybrid applications.

Advanced antennas may incorporate shielding, tuning circuits, or materials optimised for wet, metal, or curved surfaces.

RFID chip functions and memory

The RFID chip is the brain of the label. It contains:

• a unique identifier (eg EPC or UID);
• optional user memory, allowing custom data to be written;
• configuration settings, including password protection and read/write permissions;
• in some cases, cryptographic functions for authentication or secure access.

Chip memory can range from as little as 96 bits (sufficient for a unique serial number) to several kilobytes (for sensor logs or multiple data blocks). Some tags allow data to be written and updated in the field, others are locked at the factory.

Inlay manufacturers such as Impinj, NXP, Alien Technology, and EM Microelectronic offer chips with varying capabilities, including:

• tamper detection
• kill commands (to disable the tag permanently)
• read counters
• sensor inputs for temperature, moisture, or movement.

RFID inlay orientation and placement

Because RFID is a wireless technology, inlay placement and orientation affect performance. A tag that is misaligned with the reader’s antenna field may have reduced readability. Inlay placement must also avoid:

• direct contact with metal (unless designed for it)
• signal-blocking graphics or foils
• creases or folds in the label.

Correct orientation – especially for UHF – is crucial in conveyor systems, handheld scanning, and shelf-mounted readers. For NFC, which uses magnetic coupling, proximity and alignment are even more critical.

Customising RFID labels for peak performance

Not all RFID labels perform equally – nor should they. The performance of a smart label is influenced by how well it is matched to its intended purpose. This includes considerations of tag type, size, materials, adhesives, and environmental conditions.

Matching RFID tag and label size

An RFID antenna requires space to function correctly. Trying to embed a large antenna into a small label – or vice versa – leads to poor read range and inconsistent performance.

• Retail hang tags often allow space for full dipole antennas.
• Small cosmetics packaging may require miniature or embedded antennas.
• Box labels can accommodate UHF inlays in standard sizes (eg 50 × 30mm, 97 × 13mm).
• NFC labels may use circular antennas (~22mm) to enable reliable smartphone tapping.

Choosing the right antenna for the available space is the first step in RFID label customisation.

Environmental considerations

The materials and adhesive used in the label must be suited to the conditions it will face.

• On-metal environments require specially designed inlays with a spacer layer or tuned resonance.
• High-temperature areas (eg autoclaves) need heat-resistant adhesives and substrates.
• Wet or cold-chain conditions require waterproof constructions and low-temperature adhesives.
• Recyclable or compostable packaging may require solvent-free adhesives.

Having been the first Polish label printing house with a complete RFID labels production line, we partner with industry-leading material suppliers like Avery Dennison, UPM Raflatac, or Fedrigoni to match facestocks, adhesives, and liners to each project’s needs.

Adhesive choice

Adhesives must not only stick reliably, but also preserve antenna performance and comply with industry regulations.

• Acrylic adhesives – versatile, temperature-resistant and offer low-migration.
• Hot-melt adhesives – excellent for high-speed labelling lines.
• Removable or repositionable adhesives – best for reusable containers or temporary tags.
• Freezer adhesives – best for deep cold storage.
• High-tack adhesives – perfect for curved or uneven surfaces.

Some applications – such as pharmaceuticals or electronics – may require food-safe, low-migration or ISO 10993-compliant adhesives.

Facestock selection

The top material of the RFID label affects appearance, durability, and branding.

• Thermal paper – best for direct thermal printing and is economical in use.
• Glossy or matte film – PET or BOPP, ideal for premium products;
• Metallised papers – perfect for luxury look and high opacity.
• Textured stocks – best for artisanal or natural products.
• Eco-materials – such as FSC-certified or recycled papers.

Some facestocks may interact with the antenna’s field – especially metallised materials – and must be tested during prototyping.

Together, these choices define not only the functionality of the smart label, but also its compatibility with your packaging, branding, and application processes.

Visual and data design

A smart label must perform in two domains: the digital and the visual. It needs to communicate with RFID or NFC readers, but it also needs to present a clear and trustworthy visual identity to consumers, packagers, and inspectors. Integrating these two layers effectively is a core design challenge – and an opportunity for brands to stand out.

Printing and branding with intelligence

The facestock of a smart label can be printed using the same methods as conventional self-adhesive labels – such as flexography, offset printing, digital printing, or screen printing – provided that:

• the printing process does not damage the RFID inlay;
• conductive inks or metallic foils do not interfere with antenna performance; and
• the tag is tested post-printing to ensure functionality.

Designers must work closely with RFID label manufacturers to plan for:

• clear scan zones – avoiding overprinting or layering on top of the antenna field;
• iconography and cues – such as NFC or RFID symbols, instructing the user where to scan or tap; or
• dual-technology support – combining RFID, NFC, QR codes, and human-readable text.

Visual elements such as logos, authenticity icons or ‘tap here’ markers can increase interaction rates and improve consumer confidence.

Dual identifiers – barcodes, QR codes, and fallback options

To ensure interoperability and redundancy, many RFID labels include:

• GS1 barcodes (EAN-13, GS1-128, or DataMatrix), encoded with the same EPC as the RFID chip;
• QR codes, linked to marketing, product manuals, or support platforms; and
• human-readable codes, allowing manual lookup when scanning fails.

These fallback features ensure that the label remains usable across multiple systems – including those not yet RFID-enabled.

For example:

• A logistics label may include a UHF RFID inlay, a serialised barcode, and a printed SSCC (Serial Shipping Container Code).
• A spirits label may include an NFC tag and a QR code linking to a digital provenance platform.
• A cosmetics label may carry both a scannable GS1 DataMatrix and a concealed NFC tag for loyalty activation.

Variable data and personalisation

Smart labels offer powerful personalisation opportunities, including:

• serialisation – each label carries a unique identifier;
• custom URLs or tokens – directing users to personalised landing pages;
• time-sensitive codes – for promotions, warranty, or traceability;
• track-and-trace integration – showing journey or origin data upon scan.

These features enable engagement at a granular level – down to the individual unit – and support authentication, loyalty, and anti-fraud efforts.

By combining compelling visual design with machine-readable logic, brands can transform their self-adhesive labels from static identifiers into interactive, secure, data-driven interfaces.

RFID encoding and quality assurance

RFID label’s effectiveness depends not only on its materials and design, but also on its data integrity. A chip that is improperly encoded, unreadable,or linked to the wrong database may cause operational delays, inventory errors, or brand damage.

That is why encoding and quality assurance (QA) are critical steps in the smart labelling workflow.

Encoding: when and how

Encoding refers to writing data onto the RFID chip – typically a unique serial number, product code, or link. This can occur at several points:

• during inlay manufacture – the chip is pre-encoded with a static identifier;
• during integration into a RFID label – tags are encoded as labels are printed;
• inline on the packaging line – dynamic data is written at the point of application; or
• post-application – labels are scanned and linked after attachment.

The choice depends on the business need:

• Pre-encoding ensures consistency and speed for large runs.
• Inline encoding allows dynamic personalisation (eg expiry dates, serial numbers).
• Post-encoding suits systems where packaging is triggered by scanned orders.

Encoding is typically done using:

• RFID printers (eg Zebra, Sato, Toshiba)
• inline automatic applicators
• handheld encoders for small batches.

Each system must support the required protocols (eg EPC Gen2, ISO 15693), and ideally, verify that encoding was successful.

Data to encode

Typical encoded fields may include:

• EPC or UID
• GTIN (Global Trade Item Number)
• batch or lot code
• serial number
• expiry or production date
• URL or token for authentication.

For supply chains using GS1 standards, encoding must follow defined data structures to enable interoperability.

Quality assurance: more than just reading

Tag performance must be verified at several stages to avoid defective or unreadable labels entering circulation.

QA steps may include:

• Read testing – checking whether the tag responds at expected distance.
• Encoding verification – confirming that correct data is written.
• Void detection – ensuring no empty or duplicate tags remain.
• Visual inspection – especially where antennas are printed or embedded.

Advanced systems can:

• detect antenna damage caused during conversion;
• detect shorts or open circuits; and
• reject defective tags automatically.

In high-security applications – such as pharmaceutical or luxury packaging – tamper-evident tags may also be tested for functionality before and after packaging.

Here at Comex RFID we offer 100% tag validation as part of our RFID label manufacturing process, along with detailed reporting for compliance and traceability.

RFID label integration and application

Once a RFID label has been designed, printed, and encoded, it must be applied accurately and reliably to the product or packaging. This stage – often overlooked – is critical to ensuring that the label functions properly throughout the product’s lifecycle.

Whether the labels are applied by hand or using automated machinery, several factors influence success: applicator compatibility, material behaviour, tag position, curvature, and speed.

Conversion into usable formats

Before application, RFID labels are usually converted into rolls or sheets. This process involves:

• die-cutting the label into its final shape;
• matrix stripping to remove waste material around the label;
• laminating over sensitive elements, if needed; and
• rewinding into rolls of consistent tension and orientation.

RFID labels manufacturers must handle RFID inlays carefully to avoid:

• bending or snapping antenna structures;
• static discharge that can damage chips; and
• uneven liner tension, which may interfere with automated feeding.

Label printing companies experienced with RFID will use:

• inlay-friendly dies to reduce stress on the chip area;
• conductive-safe processes to minimise static; and
• RFID label verification systems to reject damaged tags in-line.

Application systems: smart vs blind

Label application systems fall into two categories:

• RFID-aware applicators, which can detect and verify tags during application; and
• blind applicators, which apply labels without knowing whether the tag functions.

For high-value or compliance-sensitive applications, RFID-aware systems are preferred. These can:

• read and confirm the tag before applying;
• adjust label position based on tag location; and
• log encoding or QA results for each label applied.

Blind applicators are more economical and may be suitable for:

• packaging with additional post-scan QA; or
• environments where RFID is supplementary to other identifiers.

Challenging surfaces and speeds

The substrate to which a label is applied affects adhesion, readability, and durability.

• Curved surfaces, such as bottles or tubes require flexible facestocks and strong adhesives.
• Rough cartons, may require high-tack or hot-melt adhesives.
• Foil or metallised packaging may interfere with RFID signals.
• High-speed lines have tight lolerances for label orientation and placement.

In some cases, a RFID label may be applied inside a package (eg within a cap, box, or blister), or combined with a security seal or tamper-evident layer. These methods require careful calibration to ensure the tag’s signal is not blocked or degraded.

Packaging engineers and RFID labels manufacturers like Comex RFID must work together to simulate real conditions like temperature, moisture, and mechanical stress – to validate performance.

Proper integration into the packaging line ensures that RFID labels deliver not only digital value, but physical reliability.

RFID labels case examples: wine bottle, logistics box, pharma blister

To illustrate the diversity of RFID label design and function, let us examine three representative examples from different industries. Each shows how RFID label construction, encoding, and application must be adapted to the context.

A. NFC tamper-evident seal for premium spirits

Use case: A producer of small-batch whisky wants to protect against counterfeiting and engage customers through their smartphones.

Label solution:

• NFC tag embedded in the bottle neck seal;
• dual-layer construction that breaks upon opening;
• carefully selected facestock for premium appearance;
• AES-encrypted chip linking to blockchain-based authentication; and
• dynamic URL encoding for region-specific promotions.

Performance requirements:

• secure, single-use chip with tamper detection;
• reliable smartphone scanning, even through protective caps;
• readable even when cold or wet (bar environments); and
• visual design matching luxury brand identity.

B. UHF RFID supply chain label for a logistics carton

Use case: A European fashion retailer ships products to stores from central distribution centres and wants to automate receiving and inventory.

Label solution:

• thermal-transfer printable label with UHF RFID inlay;
• 96-bit EPC encoding (GS1-compliant);
• standard size (100 × 150mm) compatible with pallet and item scanning; and
• applied inline during box sealing.

Performance requirements:

• readable from fixed dock-door portals and mobile readers;
• fast encoding and printing speeds;
• resistance to abrasion and shipping conditions; and
• cost-efficient for high volumes (millions per month).

C. HF RFID label for pharmaceutical blister packaging

Use case: A medical device manufacturer needs to track units of prescription therapy through distribution to hospital storage and patient use.

Label solution:

• small HF tag embedded in the rear of a blister card;
• low-migration, pharma-compliant adhesive;
• human-readable lot number and GS1 DataMatrix barcode; ad
• memory includes expiry date and device code.

Performance needs:

• compatibility with automated hospital cabinets;
• readability in close range (5–10cm);
• compliance with MDR and EU traceability regulations; and
• validation under ISO 13485 QA process.

These case studies demonstrate that no single RFID label construction is universal. Material selection, antenna type, encoding logic, and QA strategy must be tailored to the application – a process best done in collaboration with an experienced RFID labels manufacturer.

Sustainability and material innovation

As RFID labelling becomes more widely adopted, questions around its environmental impact are increasingly important. While the core function of UHF and NFC tags is technological, their material footprint – substrates, adhesives, liners, and inks – matters just as much in the broader push for sustainable packaging.

Fortunately, the industry is responding with a range of innovations aimed at reducing environmental impact without sacrificing performance.

Paper-based and recyclable RFID inlays

Traditional RFID antennas are etched from aluminium or printed with copper on plastic substrates (usually PET). However, next-generation inlays now use:

• compostable substrates, eliminating plastic film; and
• etching-free manufacturing, which reduces chemical use and energy consumption.

These inlays maintain acceptable read performance while significantly lowering carbon footprint. Brands pursuing circular economy goals can now specify these eco-designed components.

Adhesives and facestocks

Adhesives can be formulated to support recycling, food safety, and compostability. Developments include:

• solvent-free adhesives, reducing VOC emissions;
• recyclable adhesives, which do not contaminate paper streams; or
• certified compostable adhesives, used in organic food and natural products.

Facestocks, too, can support sustainability by using:

• FSC-certified or post-consumer recycled content;
• biodegradable films such as PLA; or
• low-carbon footprint synthetic materials.

RFID labels can now look and feel as eco-conscious as the brands they represent.

Release liner recycling

One of the most overlooked components of labelling is the release liner – the silicone-coated paper or film that supports the label before application. Traditionally, these liners go to landfill or incineration, creating significant waste.

Leading RFID labels manufacturers and material suppliers now offer:

• PET liners, which can be recycled more easily than glassine; and
• linerless label options, for certain formats.

Integrating these practices reduces waste and strengthens sustainability narratives in B2B supply chains.

Energy and emissions reduction

RFID label production, like all manufacturing, consumes energy. However, UHF and NFC also reduce environmental impact in other ways:

• More accurate inventory = less overproduction and waste.
• Digitally connected products = fewer printed inserts and manuals.
• Improved traceability = better end-of-life management and recalls.

Sustainability in smart labelling is not just about materials – it is about system-wide efficiency. When implemented correctly, RFID helps brands reduce emissions, lower returns, and improve transparency – all key levers in the journey to net zero.

Closing thought: it’s what’s inside your RFID label that counts

RFID labels are deceptively simple in appearance. Yet beneath the surface lies a carefully engineered, multi-layered system – one that enables wireless communication, traceability, interactivity, and security.

Understanding how these labels are constructed – from facestock to chip – is essential for successful implementation. The choices you make at each level affect not only technical performance, but also cost, compatibility, and brand experience.

As this chapter has shown:

• The RFID inlay is the heart of the RFID label, and must be matched to your use case.
• The label’s construction – adhesives, face materials, form factors – determines how it behaves in the real world.
• Encoding and QA ensure data integrity and usability.
• Application and conversion bring the label to life, connecting design with deployment.
• Sustainability innovations allow brands to embrace intelligence without compromising on environmental responsibility.

RFID labels are not a commodity. They are a convergence of material science, electronics, information systems, and customer experience. And when executed well, they transform packaging from a passive carrier into an active enabler of value.

In the next articles, we will see how these principles are applied across industries – from logistics to luxury goods – and how smart RFID labels are already delivering measurable impact at scale.