Pneumograph
Breathing
Two tubes rest across the chest and abdomen and record the depth and rhythm of each breath. People hold their breath without noticing; the chart notices.
Locations › London
Lie detector test in London
14 private examination offices across London. £495 all inclusive, conducted by an accredited examiner, with the written report within 24–48 hours. Wherever you start in London, the examiner, the format and the fee are the same — that is the point of running them all through Lie Detector UK.
£495
All inclusive
£150
Deposit to reserve
95–98%
Accuracy of a validated test
24–48 hrs
Written report
Offices
Where you can be seen in London
Croydon
81-85 Station Road CR0 2RD
View office →Kingston upon Thames
20-26 Tolworth Broadway, Surbiton KT6 7EL
View office →London – Berkeley Square House
Berkeley Square, London W1J 6BD
View office →London – Cabot Square
25 Cabot Square, Canary Wharf, London E14 4QZ
View office →London – Chiswick Park
Chiswick Park, 566 Chiswick High Road, London W4 5YA
View office →London – Covent Garden
60 St Martin’s Lane, Covent Garden, London WC2N 4JS
View office →London – Finsbury Market
1 Finsbury Market, Liverpool Street, London EC2A 2BN
View office →London – Golden Cross House
8 Duncannon Street, London WC2N 4JF
View office →London – Hammersmith
77 Hammersmith Road, Hammersmith Broadway, London W14 8UZ
View office →London – Hanover Square
17 Hanover Square, Mayfair, London W1S 1BN
View office →London – King’s Cross
16 Upper Woburn Place, King’s Cross, London WC1H 0AF
View office →London – Moorgate
30 Moorgate, City of London, London EC2R 6PJ
View office →London – More London Riverside
3 More London Riverside, London Bridge, London SE1 2RE
View office →London – Paddington
2 Kingdom Street, Paddington, London W2 6BD
View office →Every office, compared
Choosing between the offices in London
All 20 are within a ten-minute walk of a railway station; London – Covent Garden and London – Golden Cross House are under a mile apart, so one covers for the other.
| Office | By train | Parking | Next nearest |
|---|---|---|---|
| Bromley BR1 1LU | Bromley South station, about 2 min walk | Public parking within half a mile | Hayes (Bromley) 2 miles |
| Croydon CR0 2RD | West Croydon station, about 1 min walk | Public parking nearby: Derby Car Parking and Whitgift Car Park | Hayes (Bromley) 5 miles |
| Hayes (Bromley) BR2 7AL | Hayes station, about 8 min walk | Bromley 2 miles | |
| Kingston upon Thames KT6 7EL | Tolworth station, about 7 min walk | Croydon 8 miles | |
| London (Whitechapel) E1 7QA | Aldgate station, about 2 min walk | Public parking nearby: Minories Car Park | London – Finsbury Market under a mile |
| London – Berkeley Square House W1J 6BD | Green Park station, about 5 min walk | Public parking nearby: Barlow Place Car Park | London – Hanover Square under a mile |
| London – Cabot Square E14 4QZ | Canary Wharf station, about 3 min walk | Public parking nearby: Cabot Square Car Park and Canary Riverside Parking | London (Whitechapel) 2 miles |
| London – Chiswick Park W4 5YA | Gunnersbury station, about 4 min walk | Public parking within half a mile | London – Hammersmith 3 miles |
| London – Covent Garden WC2N 4JS | Leicester Square station, about 1 min walk | Public parking within half a mile | London – Golden Cross House under a mile |
| London – Finsbury Market EC2A 2BN | London Liverpool Street station, about 5 min walk | Public parking nearby: Finsbury Square Car Park and Clere Street Car Park | London – Moorgate under a mile |
| London – Golden Cross House WC2N 4JF | Charing Cross station, about 1 min walk | Public parking within half a mile | London – Covent Garden under a mile |
| London – Hammersmith W14 8UZ | Kensington (Olympia) station, about 4 min walk | Public parking nearby: Olympia London Motorail (P4) Car Park and Store Car Park | London – Paddington 2 miles |
| London – Hanover Square W1S 1BN | Bond Street station, about 2 min walk | Public parking nearby: Oxford Street Car Park | London – Berkeley Square House under a mile |
| London – King’s Cross WC1H 0AF | Euston station, about 3 min walk | Public parking nearby: Woburn Place Car Park and Judd Street Car Park | London – Hanover Square 1 mile |
| London – Moorgate EC2R 6PJ | Moorgate station, about 3 min walk | Public parking nearby: Finsbury Square Car Park | London – Finsbury Market under a mile |
| London – More London Riverside SE1 2RE | London Bridge station, about 5 min walk | Public parking nearby: Butlers Wharf car park and Snowsfields car park | London (Whitechapel) under a mile |
| London – Paddington W2 6BD | Paddington (Circle and Hammersmith & City lines) station, about 3 min walk | Public parking nearby: Paddington Station Car Park | London – Hanover Square 2 miles |
| Orpington BR6 0JX | Orpington station, about 8 min walk | Public parking within half a mile | Hayes (Bromley) 4 miles |
| Wanstead E11 2AH | Wanstead station, about 5 min walk | London – Cabot Square 6 miles | |
| Watford WD17 1JJ | Watford Junction station, about 7 min walk | Public parking nearby: Sutton Road Car Park and Gade Car Park | London – Chiswick Park 12 miles |
20 of the 20 have more than one railway station within reach, so a closure on one line is rarely a reason to move an appointment; Croydon is on a tram network; and there is free public parking within walking distance at London – Hammersmith. Across the region there are 694 public car parks within half a mile of an office.
If several people are travelling from different directions, London – Golden Cross House sits closest to the middle of the region.
Just over the border
The most isolated office here is Watford — its closest neighbour is London – Chiswick Park, 12 miles away. Everywhere else, a second room is nearer than that if the first does not suit you.
Choosing an office
They are all the same examination
The office you pick changes your journey, not your appointment. Same examiners, same instruments, same £495. Pick on travel and on which building suits you.
Nearest is not always best
If you would rather not be seen locally, book a neighbouring office instead. Nobody is told which office you chose or why.
Parking and stations are listed
Each office page states its nearest station and its parking arrangement, so you can judge the journey before you reserve anything.
A private office, never a public space
Every office is by appointment only and vetted for discretion. Examinations are conducted under strict data protection protocols.
The date is settled afterwards
The £150 deposit reserves the appointment. You can leave the exact date open and agree it with your examiner on the call.
What is actually recorded
A polygraph is a recorder, not a lie meter.
Four channels run continuously for the whole examination. No single reading decides anything — the examiner scores the pattern across all of them, against your own baseline answers.
Cardiovascular
Pulse and blood pressure
A cuff on the upper arm tracks pulse rate and relative blood pressure through the examination, not just at the moment a question is asked.
Electrodermal
Skin conductance
Two fingerplates measure the sweat glands’ response, which shifts within seconds of a relevant question and is not something a person can consciously hold still.
Activity sensor
Movement and countermeasures
A pad in the seat records movement, including the small deliberate kind — pressing the toes into the floor, tensing a muscle, altering the breath on purpose. Attempts to influence a chart show up here as steps that belong to none of the other channels, which is exactly why the channel exists.
Each examination is limited to three relevant questions, agreed with you before the instrument is attached. You will not be asked anything you have not already seen.
London · common questions
The questions people actually ask us
How accurate is a lie detector test?
A validated technique, run properly by an accredited examiner, sits at 95–98%. Anyone quoting 100% is selling you something else.
Does being nervous affect the result?
No. Nervousness is expected and shows up on every chart. The analysis compares your responses against each other, not against a calm stranger.
What questions will be asked?
Up to three relevant questions, agreed with you in the pre-test consultation. Nothing is asked on the day that you have not already seen.
Can I refuse to take the test?
Yes, at any point, including once you are in the room. An examination in the UK cannot proceed without your written consent.
How long does the test take?
Around two hours in total. Most of that is the consultation and question review; the instrument phase is the shortest part.
Can I attend someone else’s test?
No — a third party in the room invalidates the examination. You are welcome to wait in reception and to see the written report if the examinee consents.
Do you offer home or on-site tests?
Tests are normally conducted at our private office in London, where the environment can be controlled. Alternative locations may be possible subject to pre-approval.
Do you test under 18s?
Only in limited circumstances, with the written consent of a parent or guardian, and at the examiner’s discretion. Please call to discuss before booking.
Do medications affect the results?
Tell your examiner what you take. Most prescriptions are fine; a few are not, and your examiner will say so before you pay the balance.
Can the test be cheated?
Countermeasures are what examiners are trained to spot. Attempting them typically produces an inconclusive result, not a pass.
How much does a lie detector test cost in London?
£495 all inclusive for one person and £695 for a couple, covering the consultation, the examination and a written report. A £150 deposit reserves the appointment.
