Biometric Time Clocks Explained: Fingerprint vs Facial Recognition
Biometric time clocks are increasingly used by employers to improve the accuracy and security of employee time tracking by verifying identity through unique physical characteristics. In most workplace settings, this technology takes the form of fingerprint scanning or facial recognition, each offering distinct advantages and challenges. This article explains how biometric time clocks work, compares fingerprint and facial recognition systems, and examines their suitability for different working environments, with particular attention to hygiene, intrusiveness, and UK GDPR compliance. It also outlines the key legal considerations organisations must address before implementing biometric attendance systems and how these tools integrate with modern HR software.
What Are Biometric Time Clocks?
Biometric time clocks are employee time-tracking systems that use an individual’s unique physical characteristics to identify and authenticate them before recording their start and finish times. These biometric identifiers can include fingerprints, facial features, retinal or iris patterns, and hand geometry, all of which are unique to each person and can be used as secure authentication templates.
In practice, however, most workplace biometric time clocks rely on fingerprint scanning or facial recognition. More advanced biometric methods, such as retinal or iris scanning, are typically considered excessive for use with time & attendance software and are usually reserved for high-security environments such as laboratories, security services, or military facilities.
How Fingerprint Time Clocks Work
A fingerprint time clock functions on the basis that every person has a unique fingerprint pattern. This uniqueness allows fingerprints to be used as a biological identifier to accurately confirm an employee’s identity when clocking in or out of a biometric attendance system.
In practice, the biometric attendance system captures and securely stores a digital fingerprint template when the employee enrolls into the system. When an employee places their finger on the scanner, the system compares the live scan with the stored template. If the two match, the employee is authenticated and the time clock records the start or end of their working period accordingly.
How Facial Recognition Time Clocks Work
A facial recognition time clock authenticates employees by analysing unique facial features, such as the distance between the eyes, nose shape, and facial contours. These characteristics are converted into a mathematical biometric time clock record, which is used to identify an individual when they clock in or out of the biometric attendance system
In practice, an employee first enrolls by allowing the biometric time clock system to capture their facial image. The software then creates a secure biometric template rather than storing a photograph. Employees clocking in present themselves to the camera, the system compares their live facial scan to the stored template. If there is a match, the employee is authenticated and their working time is recorded and synced with employee time & attendance software.
Fingerprint vs Facial Recognition: Key Differences
Both fingerprint and facial recognition systems are widely used forms of biometric authentication, but they differ in how they operate, how intrusive they feel to employees, and how they are viewed under UK GDPR.
Contact vs Touchless Time Clock
Fingerprint recognition requires employees to physically touch a scanner to record their fingerprint, while facial recognition is a touchless time clock that uses a camera to analyse facial features such as the distance between the eyes, nose, and jawline to create a biometric template.
Hygiene; fingerprint vs facial recognition
Because facial recognition-based attendance tracking is a touchless time clock system, it is generally more hygienic than fingerprint scanning, an advantage highlighted during COVID, and can be more reliable in hands-on working environments where dirt, moisture, or gloves can prevent fingerprint scanners from reading prints accurately.
Perceived Intrusiveness
While there are privacy concerns for both, the perceived intrusiveness is considered higher with facial recognition. Concern has been expressed by employees time and time again about how their facial recognition data is stored and used, and it can feel more like surveillance. Under GDPR it is likely that it will require both a stronger justification for use than fingerprint scanners along with more robust safeguards.
Working environment: fingerprint vs facial recognition
A biometric fingerprint attendance machine is generally used in shift-based roles, manufacturing environments and retail, whereas facial recognition systems are reserved for high-security and closely controlled environments.
Biometric GDPR and Privacy Considerations
Biometric data is classed as “special category data” under GDPR, and as a result it must be processed in line with strict legal requirements. These are set out on the Information Commissioner’s Office (ICO) website, and we have summarised the key points below.
- The law requires employers to identify a lawful basis for processing biometric data.
- There are six lawful bases for processing personal data: consent, contract, legal obligation, vital interests, public task, and legitimate interests.
- In some situations, businesses may rely on consent to process special category data such as biometrics.
- Where consent is used, it must be specific, informed, and freely given, and individuals must be able to withdraw it.
The government provides a helpful hypothetical case study involving a gym to explain how consent may be used when implementing biometric systems. In this example, the gym wishes to replace swipe-card access with a facial recognition system to improve customer experience and speed of entry.
Given this objective, the gym can only rely on explicit consent to use a biometric time clock and process this special category data. This involves clearly explaining why the data is being processed, how it will be used, and informing customers of their right to withdraw consent at any time.
Customers are then asked to confirm their agreement through a clear and specific consent statement, alongside an accessible process for refusing consent. This example provides only a broad outline, and organisations should consult the ICO’s guidance when designing biometric data processing procedures.
Caution
In most workplace situations, employers cannot safely rely on employee consent to use biometric fingerprint time clocks. This is because GDPR requires consent to be freely given, and within an employment relationship there is usually an imbalance of power. As a result, employee consent is often considered invalid. This position is reflected in recent case law.
Instead, an employer may only lawfully require the use of a biometric fingerprint time clock if they can demonstrate compliance with strict GDPR conditions for processing special category data. This includes showing that biometric use is necessary, proportionate, and justified, that no less intrusive alternative is available, and that appropriate safeguards are in place.
Failure to comply with GDPR when implementing biometric time clock systems can result in regulatory fines, legal action, reputational damage, and employee relations issues, as demonstrated by several high-profile enforcement cases.
This is an opinion and does not constitute legal advice, and organisations should seek specialist GDPR advice before implementing biometric systems in the workplace.
Integrating Biometric Time Clocks with HR Software
The process of integrating the biometric timeclock with HR software is simple from a user point of view. These days many HR software providers offer pre-integrated biometric HR technology which seamlessly syncs with their online time and attendance software. Employers don’t have to procure their biometric HR technology devices from their HR provider though; they can shop around and bring their own. However, there will need to be some careful planning to ensure compatibility with your chosen biometric HR technology device and your preferred piece of online time and attendance software.
Reputable biometric systems will clearly demonstrate their GDPR compliance with encrypted biometric data and minimalist data storage with transparent audit trails and reporting.
Which Biometric Time Clock Is Best for Your Business?
Selecting the right biometric clock-in systems for companies depends on workforce size, workplace environment and privacy requirements.
Fingerprint-based systems work well in office, retail and standard industrial environments where hands are generally clean in the course of work and gloves are not worn. They’re usually more affordable and straightforward to implement in such environments.
Facial recognition systems are perfect clock-in systems for companies with hygiene-conscious working environments such as healthcare or food production or high-security areas where touchless time clocks and speed are priorities.
Some biometric time clock systems can combine fingerprint and facial recognition offering flexibility and redundancy should one system malfunction.
GDPR-compliance and fluency with GDPR regulations is critical when deciding on your biometric time clock given that you are working with special category data.
FAQ?
A biometric time clock is an employee time tracking system which uses unique physical features to authenticate and record when an employee starts and finishes a shift. The most used types of biometric time clocks are built around fingerprint scanners and facial recognition systems which use unique fingerprint or facial characteristics to identify the employee.
The answer is not straightforward.
Fingerprint data is classed as “special category data” under the UK GDPR, which means it is subject to much stricter rules than ordinary personal data.
In most workplace situations, employers cannot rely on employee consent to use biometric fingerprint time clocks. This is because consent under GDPR must be freely given, and in an employment relationship there is usually an imbalance of power. As a result, consent is often considered invalid. This recent Case Law Ruling helps to explain this.
Instead, an employer may only lawfully require the use of a biometric fingerprint time clock if they can demonstrate that they meet very strict GDPR conditions for processing special category data. These include being able to show that biometric use is necessary, proportionate, and justified, and that no less intrusive alternative is available.
To lawfully deploy a biometric fingerprint system, an employer would need to demonstrate that they have:
– A clear and compelling reason for using biometrics
– Shown that biometric processing is necessary and proportionate
– Demonstrated that no less intrusive alternative (such as cards or PINs) would work
– Completed a Data Protection Impact Assessment (DPIA)
Put in place strong safeguards, including secure storage, minimal data retention, and limited access If these conditions are not fully met, an employee may have reasonable grounds to refuse to use a biometric fingerprint time clock. Even where these conditions are met, UK regulators and case law generally expect employers to offer a non-biometric alternative wherever possible. This information is for general guidance only and does not constitute legal advice. For more information about privacy laws and rights consult the Information Commissioners website
Yes. Fingerprint scanners are a well-established and trusted form of identity authentication. Fingerprint time clocks provide a reliable and accurate method for tracking attendance, particularly in large, shift-based workforces. They are widely used and effective across industries such as manufacturing, security, the military, healthcare (NHS), and other sectors with strict compliance requirements.
It depends on the context. Biometric time clocks use special category data under UK GDPR, so best practice is that employers should only use them where there is a clear and compelling business reason, no less intrusive alternative is suitable, and the data is stored securely and minimally.
When deployed appropriately, employers should procure biometric time clocks from trusted, GDPR-compliant vendors. These systems authenticate employee attendance using biometric templates such as fingerprints or facial recognition. They are particularly effective for managing employee attendance accurately and securely in large or shift-based workforces, including retail, hospitality, manufacturing and the NHS.
For employees, using a biometric time clock is straightforward. You first register by allowing the system to scan your fingerprint (or other biometric). After registration, you simply scan your fingerprint when starting and finishing work, and the system automatically records start or leaving time in your organisation’s time & attendance software.
A biometric fingerprint clocking in system uses a fingerprint scanner to capture and store a unique biometric template for each employee. When an employee clocks in, they place their finger on the scanner, which compares the live scan with the stored template. If the two match, the employee’s identity is verified, authentication is completed, and the time clock recorder logs the start of the working session and syncs the data in real-time or periodically with your time & attendance software.
Advantages: A biometric fingerprint clocking in machine provides a convenient and secure method of human authentication. It is widely used for unlocking phones, banking apps, NHS apps, and increasingly in the workplace through fingerprint-based biometric time tracking systems. At work, these systems help businesses accurately record attendance and working hours, making payroll management easier, especially for large, shift-based workforces in industries like retail, hospitality, and manufacturing.
Disadvantages: The main drawback of a biometric fingerprint clocking in machine is privacy. Fingerprints are classified as “special category data” under GDPR, which means employers must follow strict rules when using fingerprint-based systems. Failure to comply can lead to regulatory fines, legal action, bad publicity, and damage to employee relations. Several high-profile cases have shown that misuse of fingerprint technology in the workplace can have serious consequences.
Biometric systems are often more efficient than a traditional time clock recorder, but their main drawbacks relate to privacy and compliance. A biometric time clock record includes data such as fingerprints or facial characteristics, which are classed as special category data under UK GDPR and must be handled with particular care. This creates additional legal and administrative hurdles for employers, including stricter justification, secure storage, and clear employee safeguards. Biometrics have at times proved controversial in practice, with certain high-profile employers found to be in breach of GDPR when using them, leading to regulatory action, negative publicity, and strained employee relations.
Industries that benefit most from biometric attendance systems are those with large, shift-based or mobile workforces where time theft and buddy-punching are common risks. Manufacturing, construction, healthcare, retail, hospitality, logistics and warehousing all gain from accurate clock-ins, faster payroll processing and improved compliance, while schools and public sector organisations use biometrics to strengthen safeguarding and audit controls. Hygiene conscious environments often adopt systems with employees clocking in using touchless facial recognition based biometric devices. Biometric fingerprint attendance machines remain the standard tool of use for most industries, however.
