Understanding Your Home Blood Pressure Readings
How to look at a pattern of home readings, understand what the numbers can and cannot tell you, and know what to do next.
Written by Ian Murray, Cardiac Physiologist
Blood pressure naturally varies. One reading may be higher or lower than the next even when you measure carefully.
That is why home monitoring is usually more useful when you look at a pattern of repeated readings, rather than focusing on one result. A planned series taken under consistent conditions can give a clearer picture of your usual blood pressure at rest. [1–4]
This page explains how home blood pressure readings are generally assessed and what you may need to do next. It cannot tell you whether you have hypertension or whether your medication needs changing.
Quick overview
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Why one blood pressure reading is not enough
One blood pressure reading is a snapshot. Activity, stress, caffeine, talking, posture and measurement technique can all affect an individual result. [1–4]
A planned series of well-taken readings therefore gives more useful information than one isolated number.
Do not discard a reading simply because it is higher or lower than the others. Unless there was a clear measurement problem, such as an error message or significant movement, keep the result as part of your record.
If you are unsure whether your readings were collected consistently, see our How to Measure Blood Pressure at Home guide before trying to interpret the pattern.
What does a home blood pressure average mean?
For routine assessment, an average summarises a series of readings and helps avoid placing too much emphasis on the normal variation between individual results. This can help healthcare professionals assess the overall pattern. [1–4]
This does not mean that a very high reading should be ignored. See When to seek medical help below.
Different clinical protocols calculate home blood pressure averages slightly differently. Some exclude the first day's measurements before calculating the average.
The important points are to record every reading and follow the averaging method you have been asked to use. If a healthcare professional has not asked you to calculate an average yourself, you can take your complete record to them for review.
What does 135/85 mmHg mean?
You may see 135/85 mmHg mentioned when home blood pressure is assessed.
For a planned series of home measurements, an average systolic pressure of 135 mmHg or higher, or an average diastolic pressure of 85 mmHg or higher, is an important threshold used when healthcare professionals assess for hypertension. [1–4]
This threshold applies to an average from repeated readings, not one isolated measurement.
A diagnostic threshold helps healthcare professionals assess whether hypertension may be present. It is not the same as a personal treatment target. Targets can differ according to age, other health conditions and individual circumstances. [1–3]
If you have already been given a blood pressure target, use that rather than choosing one from a general online table.
Why might home and clinic readings differ?
Home and clinic blood pressure readings do not always match.
Some people repeatedly have higher readings during a healthcare appointment than they do at home. This is commonly known as the white-coat effect.
The opposite can also occur: readings may appear lower during an appointment but be consistently higher at home or on a 24-hour monitor. When this pattern is confirmed, it is known as masked hypertension. [1,2]
A difference does not automatically mean that either set of measurements is wrong. A healthcare professional may compare your home record with clinic readings or use a 24-hour monitor to clarify the pattern.
What should you do with your home readings?
Once you have completed a planned series, keep the full record.
If your readings are repeatedly higher than expected and you have not previously been assessed for hypertension, arrange to discuss them with a doctor or another qualified healthcare professional.
If you have already been diagnosed with hypertension, follow the monitoring plan and blood pressure target you have been given. If your readings are repeatedly outside that range, share the record with your healthcare professional.
Home readings are only one part of the assessment. A healthcare professional can consider them alongside clinic measurements, symptoms, medications and your medical history.
Do not start, stop or change prescribed blood pressure medication based on individual home readings unless a healthcare professional has given you specific instructions to do so. [1–3]
Do not wait to complete a planned series if you develop emergency symptoms or obtain a very high reading. Follow the safety advice below.
When to seek medical help
If your blood pressure is repeatedly much lower than usual and you feel dizzy, faint or unwell, contact a healthcare professional for advice.
Emergency symptoms
Seek emergency medical help immediately if you think you may be having a heart attack or stroke, have severe difficulty breathing, lose consciousness or have another life-threatening emergency. [1,2,5,6]
Possible warning signs include new chest pain, sudden weakness or numbness on one side of the body, facial weakness, difficulty speaking or sudden severe breathing difficulty.
Do not wait for a particular blood pressure number and do not delay seeking emergency help while repeatedly checking your blood pressure.
A very high reading when you otherwise feel well
A systolic reading of 180 mmHg or higher, or a diastolic reading of 120 mmHg or higher, is very high. [1,2]
If you obtain a reading at or above either of these levels and otherwise feel well, sit quietly for several minutes and repeat the measurement using the correct technique.
If the repeated reading remains this high, seek urgent medical advice.
A single home reading at this level does not by itself diagnose severe hypertension, but it should not be ignored.
Do not take additional blood pressure medication unless a healthcare professional has specifically advised you to do so.
Key Takeaways
A single home blood pressure reading cannot tell you whether you have hypertension.
Look at the pattern across a series of well-taken readings rather than one isolated result.
An average home systolic pressure of 135 mmHg or higher, or diastolic pressure of 85 mmHg or higher, is an important threshold when assessing hypertension. [1–4]
A diagnostic threshold is not automatically your personal treatment target.
Keep your complete record and share your readings with a healthcare professional when appropriate.
What next?
Need to collect a reliable series first?
Our How to Measure Blood Pressure at Home guide explains how to collect a useful short series and links to our free Home Blood Pressure Reading Checklist & 7-Day Log.
Already collected your readings?
Keep the complete record and share it with your healthcare professional if you are concerned about the pattern or if it needs to be reviewed as part of your hypertension care.
Important Information
This page is provided for general educational purposes only and does not constitute medical advice. Medical knowledge and guidance evolve over time, and information may change. Home blood pressure readings should not be used on their own to diagnose hypertension or another medical condition, or to start, stop or change prescribed medication without appropriate professional advice. Always seek advice from a qualified healthcare professional regarding personal health concerns, blood pressure targets or medical decisions.
For more details, please see our full Disclaimer.
References
National Institute for Health and Care Excellence. Hypertension in adults: diagnosis and management (NG136). Last updated 26 February 2026.
McEvoy, J.W., McCarthy, C.P., Bruno, R.M., et al. 2024 ESC Guidelines for the management of elevated blood pressure and hypertension. European Heart Journal. 2024;45(38):3912–4018.
Mancia, G., Kreutz, R., Brunström, M., et al. 2023 ESH Guidelines for the management of arterial hypertension. Journal of Hypertension. 2023;41(12):1874–2071.
Parati, G., Stergiou, G.S., Bilo, G., et al. Home blood pressure monitoring: methodology, clinical relevance and practical application. Journal of Hypertension. 2021;39(9):1742–1767.
NHS. Heart attack. NHS health information.
NHS. Symptoms of a stroke. NHS health information.
Content last reviewed: September 2026
Next scheduled review: March 2027
We also review content sooner when important evidence, clinical guidance or safety information changes.