Free Prostate Specific Antigen (PSA)
Private Free PSA blood test in London for £48, measuring one prostate marker with results expected in approximately 1–2 business days.
Turnaround time
1-2 business days
Biomarkers count
1
Book your test
Choose Service Type
Professional phlebotomist comes to you
+ £{{ home_visit_fee }}
Visit our clinic for your test
{{ clinic_visit_fee > 0 ? '+ £' + clinic_visit_fee : 'Free' }}
Home Visit Details
Home visits require at least 24 hours notice.
Select a clinic: Sorting by distance…
{{ clinicAddress(clinic) }}
{{ clinicAddress(selectedClinic) }}
Select a date
Select an hour
Available time slots: {{ timeSlots.length}}
Overview of the Free Prostate Specific Antigen (PSA)
The Free Prostate Specific Antigen blood test measures the unbound fraction of PSA circulating in the bloodstream.
The test contains 1 biomarker: Free Prostate Specific Antigen.
PSA is a protein produced predominantly by cells within the prostate gland.
In blood, PSA exists in both free and protein-bound forms.
Total PSA measures the combined amount, while Free PSA measures only the unbound fraction.
Free PSA is usually most informative when interpreted together with Total PSA.
The proportion of PSA that is free can sometimes help refine prostate cancer risk assessment when Total PSA is mildly or moderately elevated.
In general, benign prostate enlargement is often associated with a higher percentage of free PSA, whereas prostate cancer can be associated with a lower free proportion.
However, there is substantial overlap.
Free PSA does not diagnose or exclude prostate cancer.
Age, prostate size, benign prostatic hyperplasia, prostatitis, urinary retention, ejaculation and manipulation of the prostate can all influence PSA measurements.
A Free PSA concentration should therefore not normally be interpreted independently of Total PSA.
The percentage free PSA can be calculated by dividing Free PSA by Total PSA and multiplying by 100, provided both measurements are performed appropriately.
The result can help determine whether further GP or urology assessment may be appropriate.
PSA-based risk assessment should ultimately incorporate age, symptoms, family history, ethnicity, examination and imaging where clinically indicated.
What Does the Free Prostate Specific Antigen (PSA) Test Check?
This test measures 1 biomarker.
Free Prostate Specific Antigen
Measures the unbound fraction of PSA in the bloodstream and can provide additional prostate risk information when interpreted alongside Total PSA.
Who May Benefit From the Free Prostate Specific Antigen (PSA) Test?
Free PSA is most useful when Total PSA has already been measured or is being measured concurrently.
Men with a borderline or mildly raised Total PSA - Free PSA can provide additional information about the PSA pattern.
Men undergoing further prostate risk assessment after an abnormal PSA result - The free fraction can complement Total PSA.
Men with benign prostate enlargement and an elevated PSA - Free PSA may help place the Total PSA result in context.
Men under urology follow-up where percentage Free PSA has been requested - Serial results can contribute to specialist assessment.
Men with a family history of prostate cancer - More detailed PSA assessment may occasionally be appropriate.
Men with persistent PSA elevation requiring further evaluation - Free PSA can form one part of the risk assessment.
Men specifically advised to obtain Free PSA testing - The result is most meaningful when a clinician has identified a reason to refine Total PSA interpretation.
How to Prepare
Do not stop Finasteride, Dutasteride or another prescribed medicine simply to change the PSA result.
Recent prostate inflammation or instrumentation can materially alter PSA and may affect the appropriate timing of testing.
Symptoms and Reasons to Consider the Free Prostate Specific Antigen (PSA) Test
Free PSA is not primarily a symptom test. Prostate conditions can produce urinary symptoms, but early prostate cancer may cause no symptoms at all.
A previously elevated Total PSA result - This is one of the main reasons Free PSA is measured.
Difficulty starting urination - Urinary obstruction can occur with benign prostate enlargement and other prostate conditions.
A weak urinary stream - Reduced flow can occur as the prostate enlarges.
Needing to urinate frequently, particularly at night - Lower urinary tract symptoms become more common with benign prostate enlargement.
A feeling that the bladder has not emptied fully - This can occur with urinary obstruction.
Persistent prostate symptoms with a borderline PSA - More detailed assessment may be appropriate.
A strong family history of prostate cancer - Risk assessment may begin even before symptoms develop.
A Total PSA result that remains elevated on repeat testing - Free PSA can provide supplementary information.
Urinary symptoms are more commonly caused by benign prostate enlargement than prostate cancer, but persistent symptoms require appropriate clinical assessment.
Inability to pass urine, severe urinary pain, fever with suspected prostatitis or significant blood in the urine requires prompt medical attention.
How to Book Your Free Prostate Specific Antigen (PSA) Test
Booking your Free PSA blood test with London Blood Tests is straightforward.
Choose the Free Prostate Specific Antigen (PSA)
Select the individual Free PSA blood test.
Select your sample collection option
Choose an in-clinic blood draw or professional home or hotel phlebotomy.
Attend your appointment
A trained healthcare professional collects the required venous blood sample.
Laboratory analysis
Your serum is analysed for Free Prostate Specific Antigen.
Receive your results securely
Your authorised result is delivered securely for interpretation alongside Total PSA and your wider prostate risk factors.
When Will I Receive My Results?
The current product turnaround for Free PSA is approximately 1–2 business days after your sample reaches the laboratory.
Once received, the sample undergoes PSA analysis, laboratory quality checks and authorisation.
The result is then released securely.
Where Total PSA or another prostate investigation has been ordered separately, the complete clinical interpretation may depend on all results being available.
Understanding Your Results
Free PSA is usually interpreted relative to Total PSA rather than as an isolated concentration.
The percentage Free PSA can be calculated when both results are available.
In appropriate patients with an intermediate Total PSA, a lower percentage of Free PSA can be associated with a higher probability of prostate cancer, while a higher proportion can be associated with benign prostate disease.
These are risk relationships rather than diagnostic thresholds.
No percentage Free PSA result can confirm or exclude cancer by itself.
The result should be interpreted with age, prostate size, symptoms, family history and previous PSA values.
Where concern remains, the next steps can include repeat PSA testing, GP or urology review, prostate examination and MRI.
Why Book With London Blood Tests?
Private Free PSA testing in London - Access targeted measurement of the unbound PSA fraction.
Refines Total PSA interpretation - Free PSA can provide additional risk information.
Useful after borderline Total PSA - The marker may help determine whether further assessment is appropriate.
Relevant to prostate monitoring - Serial results can provide additional context where a clinician has requested them.
Fast results - Current turnaround is approximately 1–2 business days.
Trusted UK laboratories - Samples undergo professional PSA analysis.
Clinic and home collection options - Professional phlebotomy can be arranged.
Clear pricing - The Free PSA test costs £48.
Private Free Prostate Specific Antigen (PSA) Blood Test in London
London Blood Tests provides private Free PSA blood testing in London for men requiring more detailed prostate risk assessment.
The test costs £48 and measures one biomarker: Free Prostate Specific Antigen.
Results are expected approximately 1–2 business days after laboratory receipt.
Free PSA is most informative when Total PSA is also available.