Cost is one of the first questions people ask when considering a lie detector test or polygraph examination. The important professional question is how the quoted fee relates to the work reasonably required for a suitable, ethical and properly scoped examination.
At the Centre for Forensic Neuroscience, fees are quoted individually after the requirements of the instruction have been assessed. Relevant factors may include case complexity, case and document review, preparation, question formulation, examination time, specialist methodology, venue and travel requirements, interpreter needs, reporting, professional liaison, quality review and follow-up.
For the practical steps after that discussion, see the UK lie detector appointment guide, which explains how to request a date, choose a location and prepare the information needed for review.
Why CFN Does Not Use a Standard Fixed-Fee Model
A polygraph examination is a professional assessment rather than a standardised retail product. The amount and nature of professional work required can vary substantially between instructions.
A predetermined standard fee necessarily requires assumptions to be made about the professional time and resources an instruction will require before the individual requirements of that case are known.
The Centre for Forensic Neuroscience takes a different approach. We first determine what the instruction reasonably requires and then quote a fee proportionate to that work.
The professional standard remains constant. The scope of professional work does not.
The professional and methodological standard does not change according to the fee. Differences in fees reflect differences in the scope and resources reasonably required by individual instructions, including specialist work such as a therapeutic disclosure examination.
Factors that may affect the individually quoted fee include:
- The nature and complexity of the issue
- The number and type of questions to be examined
- Case review and documentary review
- The preparation needed before the appointment
- The location and venue arrangements
- Travel time and distance
- Examination time and any specialist methodology
- Interpreter requirements where relevant
- Reporting and quality-review requirements
- Solicitor or other professional liaison and follow-up
- Urgency, unusual logistics or international requirements
- Whether the instruction is private, legal, therapeutic or workplace-related
What May an Individually Quoted Polygraph Fee Reflect?
Depending on the agreed scope, a professional polygraph fee may reflect the following work:
- A confidential initial discussion to understand the issue
- Suitability screening to determine whether a polygraph is appropriate
- Review and clarification of the matter to be examined
- Question formulation — developing clear, testable questions
- Preparation time before the appointment
- A structured pre-test interview
- The informed consent process
- The polygraph examination itself
- Analysis and interpretation of results
- A verbal explanation of the outcome
- A written report where appropriate
- Administrative time
- Travel and venue arrangements where relevant
Not every case requires the same level of preparation or reporting. A private relationship matter may require a different scope from a solicitor-led instruction or a workplace investigation. The fee should be proportionate to the work involved.
Comparing Quoted Fees and Scope
Headline fee alone does not establish the quality of a polygraph examination. However, a predetermined standard fee necessarily involves assumptions about the professional time and resources that will be required. Individual cases do not necessarily require the same preparation, documentation, question development, venue arrangements, reporting or professional input. Clients should therefore consider not only the quoted fee, but also the scope of professional work that the fee is intended to cover.
Relevant questions include:
- How much time is spent assessing suitability before booking
- The examiner’s training and experience
- The quality and care of question formulation
- Whether written reporting forms part of the agreed scope
- Whether venue and travel costs are included
- Whether the appointment is rushed
- Whether ethical issues are properly considered
- Whether the examiner is named and accountable
Differences in quoted fees should be understood by reference to the agreed scope of work, not treated as an automatic measure of methodological quality.
For guidance on what to look for in a professional examiner, see our article on how to choose a polygraph examiner in the UK.
Why Some Polygraph Examination Fees Differ
An instruction may require a greater scope of professional work where it involves:
- A legal instruction requiring solicitor correspondence
- A workplace or employment context with HR documentation
- Multiple documents or background material to consider
- Therapeutic disclosure preparation and coordination
- Safeguarding complexity
- Agreed written reporting requirements
- Travel to a suitable venue
- Urgent scheduling
- Additional professional time before or after the examination
Private Relationship and Infidelity Polygraph Costs
Private relationship matters are often specific-issue examinations, but the scope still matters. The issue must be clearly defined, questions must be specific and behaviourally focused, and both parties should have clarity about what the examination can and cannot answer.
Coercion or pressure must be avoided — all polygraph examinations must be taken on a voluntary basis. Not every relationship dispute is suitable for polygraph testing. A professional examiner should be willing to explain the limitations and decline cases where a polygraph is unlikely to be helpful or appropriate.
For more information on relationship and infidelity polygraph examinations, see our dedicated page.
False Allegation and Legal Context Costs
False allegation matters can require additional care, especially where there are legal proceedings, solicitor involvement, police involvement, safeguarding concerns or reputational risk. The question formulation, reporting and professional context may need to be handled differently from a private relationship matter.
A polygraph examination in this context should not be treated as proof of innocence or guilt. It may provide additional investigative information where the scope is appropriate and the examination is professionally conducted. Solicitors and barristers may instruct the Centre directly where the instruction is clear and suitable.
Workplace, Theft and Internal Investigation Costs
Workplace matters may involve employer and employee consent issues, workplace policies, HR context, documentation, internal investigation scope, report requirements and potential legal or employment implications.
The quoted fee may reflect additional work where there is substantial background to review or where reporting needs to meet a specific professional or legal standard. Employers should not use a polygraph as a substitute for fair investigation or legal and HR advice. For more on workplace polygraph examinations, see our dedicated page.
Therapeutic Disclosure or Behavioural Accountability Costs
Therapeutic disclosure-related polygraph work may involve additional scoping, careful question formulation, professional boundaries and coordination with the referring therapist or treatment provider. The examination may support a disclosure or behavioural accountability process, but it is not therapy and should not replace clinical or therapeutic support.
Fees in this context may reflect the additional preparation, professional liaison with the referring clinician and the sensitive nature of the disclosure work. For guidance, see our page for therapists on disclosure statements and therapeutic polygraph.
Venue, Travel and Location Factors
The cost of a polygraph examination may depend on whether the examination is conducted at an appropriate professional venue, a meeting room, a solicitor’s office, or another suitable agreed location. Venue suitability matters because polygraph examinations require privacy, minimal interruption and appropriate conditions.
Examinations may be arranged at suitable professional venues in Manchester, Preston, London, Birmingham, Edinburgh or elsewhere in the UK, subject to availability and the nature of the instruction. In accordance with APA recommendations, examinations are not conducted in domestic settings.
Reporting: Is a Written Report Included?
Where written reporting forms part of the agreed scope, the professional time and care it requires will be reflected in the individually quoted fee. Depending on that scope, a report may include:
- The referral issue and agreed scope
- Examinee details where appropriate
- Questions presented during the examination
- Procedure followed
- Result terminology and interpretation
- Limitations and relevant caveats
- Examiner details and qualifications
Reporting requirements differ for private, legal, workplace and therapeutic matters. Whether a written report forms part of the instruction, and the extent of that report, should be discussed and agreed before the appointment is confirmed and reflected in the quoted fee.
Questions to Ask Before Comparing Fees
Before comparing polygraph examination fees, consider asking each provider:
- Who will conduct the examination?
- Is the examiner named?
- What is included in the fee?
- Is suitability assessed before booking?
- Are questions developed before the test?
- Will I see the questions before the examination?
- Is a written report included?
- Are venue and travel included?
- What happens if the case is unsuitable?
- What are the limits of confidentiality?
- How long will the appointment take?
- Are there any additional costs?
For a fuller guide, see our article on how to choose a polygraph examiner in the UK.
Cost Should Be Considered Alongside Suitability
The most important question is not whether someone can pay for a test, but whether the test is appropriate. A professional examiner should be willing to explain when a polygraph is unsuitable — and to decline a case where a polygraph would not be helpful, ethical or properly scoped.
A decision not to proceed can be a sign of professional integrity.
Learn more about how to prepare for a polygraph examination and what to expect from the process.
Why Dr Keith Ashcroft Assesses Fees Case by Case
Dr Keith Ashcroft, Principal Forensic Polygraph Examiner at the Centre for Forensic Neuroscience, assesses fees individually so that the quoted fee reflects the nature of the instruction and the professional work reasonably required. This includes:
- The issue being examined
- Complexity of question formulation
- Venue and travel requirements
- Preparation required before the appointment
- Reporting requirements
- Legal, workplace, private or therapeutic context
- Suitability and ethical considerations
This case-by-case approach is intended to ensure that clients understand the scope, quoted fee and limitations of the examination before deciding whether to proceed. To discuss your specific circumstances, contact Dr Keith Ashcroft for a confidential discussion.
Conclusion
The cost of a lie detector test in the UK is important, but it should be viewed in the context of professionalism, suitability, ethical practice, preparation, question formulation and reporting. A professional polygraph examination involves substantially more than a single appointment — it includes suitability screening, question design, informed consent, careful testing and appropriate interpretation of results.
Before choosing a provider based on headline fee alone, consider the scope of professional work included, whether the examination is suitable for your matter, and whether the examiner can demonstrate appropriate training, experience and professional standards.
Frequently Asked Questions
How much does a lie detector test cost in the UK?
The cost can vary depending on the issue, complexity, venue, travel, preparation and reporting requirements. At the Centre for Forensic Neuroscience, fees are assessed on a case-by-case basis after a confidential discussion.
Why are polygraph examination fees assessed case by case?
Each matter is different. The professional and methodological standard remains constant, while the scope and resources reasonably required for a private, legal, workplace or therapeutic instruction may differ materially.
Is the cheapest lie detector test the best option?
Headline fee alone does not establish quality. Compare the agreed scope, examiner training, suitability screening, question formulation, ethical safeguards and reporting requirements.
Does the cost include a written report?
That depends on the agreed scope. Where a written report forms part of the instruction, the reporting requirements are agreed before the examination and reflected in the quoted fee.
Can I get an exact fee before explaining the issue?
Usually, a clear fee can only be confirmed once the issue, scope, location, preparation and reporting requirements are understood. A brief confidential discussion is the first step.
Does a higher cost mean a better polygraph examination?
No. The professional and methodological standard remains constant. A different fee reflects differences in the scope and resources reasonably required, such as additional preparation, review, travel, venue arrangements, professional liaison or reporting.
Can a solicitor request a polygraph examination?
Solicitor-led enquiries may be considered where the scope is clear and the examination is suitable. A polygraph should not replace legal advice or the court’s assessment of evidence. See our page on polygraph examinations for solicitors and barristers.
Important Disclaimer
This article is provided for general educational and consumer information only. It does not constitute legal advice, therapeutic advice, medical advice, or safeguarding advice. Polygraph results are investigative information and should not be treated as absolute proof of truth or deception. They do not replace legal advice, therapy, safeguarding procedures, workplace investigations or the court’s assessment of evidence. Fee information is general guidance only; an accurate quotation can only be provided after a confidential discussion about the specific matter. No solicitor-client or professional-client relationship is created by this publication.
Dr Keith Ashcroft is the Principal Forensic Polygraph Examiner at the Centre for Forensic Neuroscience. For professional enquiries concerning polygraph examinations and fees, contact Dr Keith Ashcroft.