How to Measure Blood Pressure at Home
A step-by-step guide to taking consistent and useful blood pressure readings at home.
Written by Ian Murray, Clinical Cardiac Physiologist
Blood pressure naturally changes throughout the day. It can also be temporarily affected by exercise, caffeine, smoking, talking, stress and even the way you are sitting.
That means how you measure your blood pressure matters.
Using the same good technique each time removes many avoidable influences and makes your readings easier to compare. If you are collecting measurements over several days, consistency also gives you and your healthcare professional a more useful picture than occasional readings taken under different conditions. [1–4]
A single home blood pressure reading cannot diagnose high blood pressure. If your readings are repeatedly higher than expected, or you are concerned about them, speak with your doctor or another qualified healthcare professional.
New to blood pressure? If you want to understand what the numbers mean, why blood pressure can become high and why knowing your numbers matters, see our guide to High Blood Pressure.
Why correct technique matters
A home blood pressure monitor does not measure a fixed number that stays the same throughout the day.
Blood pressure continually changes as your body responds to activity, rest, emotions, meals, sleep and many other influences. Small differences between readings are therefore normal.
Your measurement technique can create additional differences.
For example, taking a reading immediately after walking upstairs, talking while the monitor is measuring, sitting without back support or allowing your arm to hang below heart level can all make a result less representative of your resting blood pressure.
The aim is not to make every reading identical. It is to remove as many avoidable influences as possible so that your measurements can be compared more meaningfully. [1–4]
Before you begin: use a monitor you can trust
For routine home monitoring, use a clinically validated automatic blood pressure monitor, preferably one that measures around the upper arm. [1–4]
Clinical validation means that the particular monitor model has undergone recognised testing to assess how accurately it measures blood pressure.
The cuff also needs to fit your arm correctly. A cuff that is too small or too large can affect the measurement.
If you need help choosing a suitable device, our Blood Pressure Monitor Guide explains clinical validation, cuff size, upper-arm and wrist monitors, and the additional features available on modern devices.
Once you have a monitor, follow the manufacturer's instructions for your particular model as well as the general measurement principles below.
How to take a blood pressure reading at home
Before starting, remember these four checks:
These are the same four prompts used in our free Home Blood Pressure Reading Checklist + 7-Day Log and cover many of the most common causes of inconsistent home readings.
Step 1: Prepare before measuring
Try to measure under similar conditions each time.
For at least 30 minutes beforehand, avoid smoking, caffeine and exercise. [1–4]
If possible, also avoid measuring immediately after a large meal or drinking alcohol. Empty your bladder if needed.
Then sit somewhere quiet and comfortable and rest for about 5 minutes before starting. [1–4]
Use this time to sit quietly. Avoid making phone calls, answering messages or moving around while preparing for the measurement.
What time should you measure?
If you are collecting a planned series of home readings, try to measure at approximately the same times each morning and evening.
Consistency is more important than choosing an exact minute.
If a healthcare professional has asked you to measure at a particular time, including in relation to medication, follow their instructions.
Do not delay, skip or change prescribed medication simply to obtain a blood pressure reading.
Step 2: Sit correctly
Sit on a chair with your back supported and both feet flat on the floor.
Keep your legs uncrossed and allow your hand and arm to relax. [1–4]
Remain in this position during your measurements.
Avoid sitting perched on the edge of a chair or on a stool without back support.
Step 3: Position your arm and cuff
Place the cuff around your bare upper arm, rather than over clothing.
Make sure you are using the correct cuff size and follow the positioning markings supplied with your monitor. The cuff should be secure but not painfully tight.
Support your arm on a table, desk or cushion so that it is relaxed and the cuff is approximately level with your heart. [1–4]
Do not hold your arm up using your own muscles. Supporting it helps the arm remain relaxed throughout the measurement.
Which arm should you use?
If a healthcare professional has told you which arm to use, use that arm consistently.
Blood pressure is normally checked in both arms during an initial professional assessment because some people have a persistent difference between the two. If a meaningful difference is confirmed, future measurements are generally taken from the arm with the higher pressure. [1–4]
If nobody has specified an arm for you, use the same arm consistently for your home readings and ask a healthcare professional to check both arms when appropriate.
Step 4: Take the reading
Start the monitor.
While it is measuring, stay still and quiet. Keep your arm relaxed, do not talk and avoid using your phone. [1–4]
Allow the monitor to complete the measurement.
Then wait approximately 1–2 minutes and take a second reading.
Record both readings.
If the monitor displays an error message, you move significantly during the measurement or the reading is interrupted, follow the manufacturer's instructions and repeat that measurement.
Avoid repeatedly checking your blood pressure until you obtain a number you prefer. The aim is to record what your blood pressure is under consistent conditions, not to produce a particular result.
Record your results
Write down each result as displayed. A blood pressure reading is shown as:
Systolic / Diastolic
For example:
132 / 82 mmHg
If your monitor also displays your pulse rate, you can record that too.
Do not round the blood pressure numbers up or down.
If something unusual happened that might have affected a reading, such as illness, unusual stress, significant movement or a warning symbol on the monitor, add a short note.
Keeping a complete record makes it easier to see the pattern across several measurements rather than focusing on one individual number.
How to collect a useful short series of readings
One well-taken measurement gives you a snapshot.
A planned series gives you more information because blood pressure varies from one measurement to the next and from day to day.
If you have been asked to collect home blood pressure readings, or need a clearer picture than an occasional isolated measurement, a simple approach is to:
measure for 7 consecutive days;
measure once in the morning and once in the evening;
take 2 readings each time, approximately 1–2 minutes apart; and
record every reading. [1–4]
This gives up to four readings each day.
Try to use the same arm, similar measurement times and the same good technique throughout the seven days.
Do not discard a reading simply because it is higher or lower than the others. Keeping the complete series provides more useful information than selecting the results you prefer.
Different clinical guidance uses slightly different methods for calculating a home blood pressure average. If a healthcare professional has asked you to calculate an average or follow a particular method, use the approach they recommend.
For you, the most important part is collecting the readings consistently and keeping a complete record.
Download our free Home Blood Pressure Checklist & 7-Day Log
Follow a clear step-by-step checklist, then record seven days of morning and evening readings. Print the log and complete it by hand, or type directly into the fillable PDF and save a completed copy on your device.
Longer-term home monitoring
Home blood pressure monitoring can also be useful after high blood pressure has been diagnosed.
But more measurements are not automatically better.
How often you need to measure over the longer term depends on your circumstances, treatment and what your healthcare professional needs to know. Home monitoring can form part of long-term blood pressure management alongside regular professional review. [1–4]
If you have diagnosed hypertension, follow the monitoring plan agreed with your healthcare professional rather than assuming you need to measure every day.
You may sometimes be asked to collect another short series of readings before an appointment or after a change in treatment.
Do not start, stop or change prescribed blood-pressure medication because of individual home readings unless a healthcare professional has given you specific instructions for doing so.
Home readings can provide useful information, but they are only one part of assessing blood pressure. A healthcare professional may also recommend measurements in a healthcare setting or a portable monitor that automatically records blood pressure over 24 hours.
The important point is simple:
Do not diagnose yourself with high blood pressure from one reading or one day's measurements.
Common mistakes and questions
Common mistakes to avoid
Small differences in technique can make home blood pressure readings harder to compare.
Common problems include measuring immediately after exercise or caffeine, skipping the five-minute rest, sitting with your back unsupported or legs crossed, placing the cuff over clothing, using the wrong cuff size, allowing your arm to hang down, or talking and moving while the monitor is measuring. [1–4]
Another common mistake is repeatedly retaking measurements because you do not like the result.
Consistency matters more than trying to produce a particular number.
For a practical refresher, see our guide to 5 common mistakes when taking a home blood pressure reading.
What if the two readings are different?
It is normal for your first and second readings to differ.
Blood pressure naturally varies, and the second measurement is taken after you have been sitting quietly for slightly longer. That is one reason more than one measurement is useful.
Record both readings rather than keeping only the lower one.
If a measurement was clearly affected by significant movement or an error message, follow the monitor's instructions and repeat that measurement.
If your readings remain unexpectedly different or vary widely despite using good technique, discuss the results with a healthcare professional.
Ask a healthcare professional to check your technique
If you are new to home monitoring, uncertain about your technique, or repeatedly getting results you did not expect, consider taking your monitor with you to a healthcare appointment.
A doctor, nurse, pharmacist or other appropriately qualified healthcare professional may be able to check that the cuff fits correctly, that you are positioning it properly, that your posture and arm support are appropriate and that you are using the most suitable arm consistently.
If you have been given different measurement instructions because of your individual circumstances, follow the advice provided by your healthcare professional.
Key Takeaways
Use a clinically validated monitor with the correct cuff size.
Good technique matters: prepare consistently, sit correctly, support your arm and remain still and quiet.
Take 2 readings approximately 1–2 minutes apart and record both.
For a structured home series, measure morning and evening for 7 days using the same technique.
Focus on the pattern across repeated readings, and follow any longer-term monitoring plan agreed with your healthcare professional.
When to seek medical help
This page explains how to measure blood pressure consistently. It cannot interpret an individual reading or diagnose high blood pressure.
If your readings are repeatedly higher than expected, or you are concerned about your blood pressure, contact a doctor or another qualified healthcare professional.
Very high readings
A blood pressure reading around 180/120 mmHg or higher is very high. [1,2]
If you obtain a reading around this level and otherwise feel well, sit quietly for several minutes and repeat the measurement using the correct technique.
If the repeated reading remains very high, seek prompt advice from a healthcare professional or your local urgent healthcare service.
Seek emergency medical help immediately
Seek emergency medical help if a very high blood pressure reading occurs with serious new symptoms such as chest pain, severe breathlessness, new confusion, weakness or numbness on one side of the body, difficulty speaking, fainting, major visual disturbance or other severe neurological symptoms. [1,2]
Do not delay seeking emergency help to keep repeating blood pressure measurements.
What next?
If you need a home monitor, our Blood Pressure Monitors Guide explains what clinical validation means, how to check cuff size, and which additional features may be useful.
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 to diagnose a medical condition or to start, stop or change medication without appropriate professional advice. Always seek advice from a qualified healthcare professional regarding personal health concerns 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.
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.
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.
Content last reviewed: August 2026
Next scheduled review: February 2027
We also review content sooner when important evidence, clinical guidance or safety information changes.