Employee Absenteeism and Sick Leave Fraud: Detection Strategies

The cost of sick leave fraud to UK employers

Employee absenteeism costs UK businesses an estimated £29 billion annually. While the majority of sick leave is genuine, the Chartered Institute of Personnel and Development (CIPD) reports that a third of organisations consider non-genuine absence to be a problem. Employees who call in sick while working for another employer, running a side business, or simply enjoying a day off represent a direct cost to the business and a morale problem for colleagues who cover their workload.

This article explains how employers can identify suspicious absence patterns, the legal rules governing sick leave fraud, the investigation methods available, and the steps to take once evidence of abuse has been gathered.

Recognising suspicious absence patterns

Patterns that warrant attention

Not every sick absence is suspicious, and employers must be careful not to treat genuine illness as misconduct. However, certain patterns are associated with non-genuine absence. Regular Monday or Friday absences (extending the weekend). Absences that coincide with school holidays, sporting events, or known social commitments. Absences that follow a denied holiday request. Self-certified absences that consistently stay just below the threshold requiring a GP fit note (seven consecutive days under current rules). An employee who is frequently absent but never appears unwell before or after the absence.

These patterns individually may have innocent explanations. A person with a chronic condition may genuinely be worse on Mondays due to fatigue accumulated over the week. Someone with childcare difficulties may genuinely be unwell when their children are on school holidays (viral infections circulate in households). The pattern is an indicator, not proof.

Social media indicators

An employee who calls in sick on a Friday and posts photographs of themselves at a music festival on Saturday has provided evidence that contradicts their claimed illness. Social media posts are public, and employers are entitled to consider publicly available information when assessing the genuineness of a sick absence.

Employers should not, however, create fake social media profiles to befriend absent employees, ask colleagues to monitor the employee’s social media on the employer’s behalf, or use social media evidence as the sole basis for disciplinary action without giving the employee an opportunity to explain. Social media evidence is a starting point for investigation, not an endpoint.

Whistleblower reports

Colleagues often know when someone’s absence is not genuine. A team member who sees the absent employee working at a market stall, running a food delivery service, or training at a gym on a day they claimed to be bedbound has firsthand knowledge. Encouraging employees to report concerns through a confidential channel (without creating a culture of informing on colleagues) provides useful intelligence.

Legal rules governing absenteeism

Employment law requirements

Investigating sick leave fraud is an employer’s right, but it must be exercised within the requirements of employment law. The ACAS Code of Practice on Disciplinary and Grievance Procedures applies to any investigation that may result in disciplinary action. The investigation must be reasonable in scope and conducted by an impartial investigating officer. The employee must be informed of the allegations and given an opportunity to respond before any disciplinary decision is made.

An employer who dismisses an employee for suspected sick leave fraud without investigating properly risks an unfair dismissal claim. The test under section 98 of the Employment Rights Act 1996 is whether the employer had a genuine belief in the employee’s misconduct, whether that belief was based on reasonable grounds, and whether a reasonable investigation was carried out. A knee-jerk dismissal based on a single social media post, without giving the employee a chance to explain, is unlikely to meet this test.

Disability discrimination risks

Some patterns that look like sick leave abuse may actually reflect a disability or long-term health condition. An employee with depression, chronic fatigue syndrome, fibromyalgia, or another fluctuating condition may have genuinely unpredictable absences that appear suspicious to an employer who does not understand the condition.

The Equality Act 2010 protects employees with disabilities from discrimination, including discrimination arising from disability (section 15). If the absences are related to a disability, the employer must consider reasonable adjustments before taking any adverse action. Dismissing an employee whose absences are caused by a disability, without exploring adjustments, is likely to be discriminatory.

This does not mean that a disabled employee can never be disciplined for absence. But the employer must understand the medical position, make reasonable adjustments, and ensure that any action taken is proportionate. Obtaining an occupational health report before investigating is good practice where there is any possibility that absence is health-related.

Data protection

Investigating absence involves processing personal data – attendance records, medical information (if a fit note has been provided), social media content, and potentially surveillance evidence. All processing must comply with UK GDPR. The lawful basis for processing will typically be legitimate interests (the employer’s interest in managing absence and preventing fraud). Where special category data is involved (health information), additional conditions under Article 9 apply.

Investigation methods

Attendance record analysis

The first step is to review the employee’s attendance record over a reasonable period – typically 12 to 24 months. This establishes whether there is a pattern, the total cost of the absences, and whether the employee has previously been warned about their absence levels. Pattern analysis should look at day-of-week distribution, proximity to holidays and weekends, duration of absences, and correlation with specific events or seasons.

Welfare check visits

Some employers conduct welfare check visits to absent employees, either by a manager or an occupational health adviser. These visits serve a dual purpose: demonstrating that the employer cares about the employee’s wellbeing, and verifying that the employee is at the address they claim to be. An employee who says they are at home with flu but does not answer the door over several hours raises questions. Welfare visits should be conducted sensitively and in accordance with a published absence management policy.

Surveillance

Covert surveillance is appropriate when the employer has reasonable grounds to suspect that the absence is not genuine and when less intrusive methods (welfare visits, occupational health referral, attendance management meetings) have not resolved the issue. Surveillance can confirm whether the employee is at home as claimed, whether they are involved in activities inconsistent with their stated illness, and whether they are working elsewhere during their absence.

Surveillance must be proportionate. Conducting weeks of surveillance over a minor absence concern is disproportionate and may result in the evidence being challenged in tribunal. A focused surveillance operation, two or three days at times when the employee has reported sick, is more proportionate and more likely to produce usable evidence.

The evidence from surveillance should be video or photographic, timestamped, and supported by a detailed observation log. The operative’s witness statement should record only what was directly observed, without interpretation or assumption. “Subject was observed carrying shopping bags weighing approximately 10-15kg” is factual. “Subject clearly had no back problem” is an opinion that the operative is not qualified to give.

Open-source investigation

Reviewing the employee’s public social media profiles, checking whether they are advertising services through business directories, and searching for evidence of secondary employment through Companies House (directorship searches) and business listings provides additional evidence without the cost of physical surveillance.

Referral to occupational health

Before drawing conclusions about whether absence is genuine, an occupational health referral can provide medical context. The occupational health adviser can assess whether the employee’s stated condition is consistent with their absence pattern, whether there are undiagnosed health issues the employer should be aware of, and whether reasonable adjustments could help attendance.

An occupational health report strengthens the employer’s position regardless of the outcome. If the report confirms a genuine health condition, the employer can make adjustments and manage the absence through the capacity procedure. If the report finds no medical basis for the claimed absence, the employer has medical evidence to support a disciplinary investigation.

Taking action on the evidence

Disciplinary proceedings

If the investigation produces evidence of sick leave fraud, surveillance showing activities inconsistent with claimed illness, evidence of secondary employment during sick leave, or social media posts contradicting the claimed condition, the employer should follow its disciplinary procedure. The employee must be told the specific allegations, given copies of the evidence, and given an opportunity to respond at a disciplinary hearing.

Sick leave fraud is typically treated as gross misconduct, which can justify summary dismissal (dismissal without notice). However, the employer must still follow a fair procedure. Summary dismissal without a hearing, or a hearing that is a rubber-stamping exercise rather than a genuine consideration of the evidence, risks an unfair dismissal finding.

Recovery of sick pay

If the employee received sick pay during periods of fraudulent absence, the employer may be entitled to recover those payments. The employment contract should include a provision allowing recovery of sick pay obtained through fraud. Without such a provision, recovery may be possible through a civil claim, but the process is more complex.

Criminal prosecution

In serious cases, where the fraud has been sustained over a long period, involves large sums, or includes forged medical documents, criminal prosecution under the Fraud Act 2006 is an option. The employer would need to report the matter to the police and cooperate with a criminal investigation. Criminal prosecution is relatively rare for sick leave fraud, but it sends a strong deterrent message where the evidence supports it.

Prevention through policy and culture

Investigation addresses abuse after it has occurred. A well-designed absence management policy reduces the opportunity for abuse and makes genuine cases easier to support. Good absence management includes a clear, consistently applied absence reporting procedure. Return-to-work interviews for every absence (these have been shown to reduce casual absence by up to 30 per cent). Trigger points that prompt a management review (for example, three absences in a rolling 12-month period). Access to occupational health support for employees with genuine health conditions. Flexible working arrangements that reduce the incentive for false sick reports (if an employee can take a day of annual leave at short notice, they are less likely to call in sick).

A workplace culture where attendance is valued, absences are noticed and discussed, and genuine illness is supported without stigma reduces both genuine and non-genuine absence. A culture where absence is ignored until it becomes a crisis creates the conditions for abuse.

Working with UKPI

UKPI investigates employee absenteeism for businesses across the UK. Our employee investigation services include surveillance, social media and open-source research, background checks, and directorship searches. We gather evidence to tribunal-admissible standards and produce reports that support fair and defensible disciplinary proceedings.

If you suspect an employee is abusing sick leave, call 0800 043 1754 for a confidential discussion. We will advise on the most appropriate investigation approach for your situation and provide a clear cost estimate before any work begins. You can also contact us online.