Blood Sample Collection Methods: Venous, Capillary and Arterial Blood Collection Explained

Blood sample collection methods are commonly grouped into three main routes: venous blood collection, capillary blood collection and arterial blood collection. Venous collection provides enough blood for most routine laboratory tests. Capillary collection obtains a smaller sample through a skin puncture or incision. Arterial collection, also called arterial blood sampling, is mainly used to assess oxygenation, ventilation and acid-base status.

The correct route depends on the ordered test, required volume, specimen matrix, patient condition and collection setting. The laboratory method must also be suitable for that specimen type. Convenience alone is not a safe basis for changing the collection route.

Quick answer: Venous, capillary and arterial collection are the three principal blood sampling routes. Blood culture collection, dried blood spots and catheter draws are important workflows or sample formats, but they are not additional blood sources at the same classification level.

Blood collection methods at a glance
What is blood sample collection?
How is a blood collection method selected?
Venous blood collection
Capillary blood collection
Arterial blood collection
Venous vs capillary vs arterial blood
Why microcollection tubes matter
Specimen matrices
Reliable collection principles
Frequently asked questions
LINKFAR capillary blood collection solutions
Get a quote

Blood collection methods at a glance

Collection method	Where the sample comes from	Typical volume	Common purposes	Main limitation
Venous blood collection	A vein, usually in the arm	Moderate to large	Routine haematology, clinical chemistry, immunology, coagulation, therapeutic drug monitoring and many other laboratory tests	Requires venous access and usually trained personnel
Capillary blood collection	A skin puncture or incision, usually at the fingertip or heel, or at an approved alternative site	Small to microvolume	Point-of-care testing, glucose testing, selected laboratory tests, paediatric sampling, newborn screening and validated decentralised collection	Not every analyte or method is interchangeable with venous testing
Arterial blood collection	An artery, commonly the radial artery	Small and purpose-specific	Blood gases, oxygenation, ventilation and acid-base assessment	More invasive and requires specialised collection and handling

What is blood sample collection?

Blood sample collection is the process of obtaining blood for laboratory examination, point-of-care testing, screening, diagnosis, treatment monitoring or research. It is part of the preanalytical phase, which covers everything that happens before the sample is measured.

Collection errors can affect the result even when the analytical test itself is performed correctly. Examples include collecting the wrong specimen, using an unsuitable tube, underfilling the tube, contaminating or haemolysing the sample, and failing to meet storage or transport requirements. The World Health Organization’s phlebotomy guidance describes how collection practice affects both patient safety and specimen quality.

Blood samples support many clinical tasks, including:

diagnosing or excluding disease;
monitoring chronic conditions and treatment response;
measuring blood cells, electrolytes, enzymes, hormones and antibodies;
checking coagulation status;
detecting bloodstream infection;
assessing oxygenation and acid-base balance;
screening newborns and other defined populations;
supporting clinical trials and remote health programmes.

How is a blood collection method selected?

The test requirement comes first. Device selection follows.

A laboratory or clinical team normally considers these questions:

What analyte or clinical condition is being assessed?
Does the test require venous, capillary or arterial blood?
Is whole blood, plasma, serum or a dried specimen required?
How much blood is needed for the test and any repeat analysis?
Does the collection tube require an anticoagulant, clot activator, preservative or separator?
Are collection time, fasting, posture, oxygen therapy or medication timing relevant?
What are the patient’s age, weight, circulation and vascular-access considerations?
Will the sample be tested immediately, transported locally or shipped to a remote laboratory?
Has the full collection and analytical workflow been validated for that specimen type?

The decision sequence is:

Test requirement -> specimen requirement -> collection route -> device and container -> handling and transport

This order matters. A collection device cannot make an unsuitable specimen type appropriate for a test.

1. Venous blood collection

Venous blood collection, or venipuncture, uses a needle to enter a vein and collect blood into one or more tubes. It is the standard route for most routine laboratory testing because it can provide several millilitres of blood for multiple tests, repeat measurements or different specimen matrices.

Common uses of venous blood

Venous specimens are widely used for:

complete blood counts and other haematology tests;
routine chemistry panels;
liver, kidney, lipid and metabolic testing;
immunology and serology;
hormone testing;
coagulation studies;
therapeutic drug monitoring;
molecular testing;
blood cultures and other specialised investigations.

Common venous collection systems

Venous blood may be collected with:

an evacuated tube system with a straight needle and tube holder;
a winged blood collection set, often called a butterfly set;
a syringe and an appropriate blood-transfer device when clinically indicated;
an existing vascular access device when an approved institutional procedure permits it.

The needle, tube, additive and required fill volume must suit the intended test. Cap colour alone does not confirm suitability because colour conventions and formulations can vary between manufacturers and markets.

Advantages and limitations

Venous collection supports a broad test range and can provide enough blood for several tubes. Laboratories also have established methods and reference intervals for many venous specimens, including whole blood, plasma and serum.

It usually requires trained personnel and can be difficult in patients with poor venous access. Patients may experience anxiety, bruising or vasovagal reactions. Used needles also create an exposure risk if safe practice and protective devices are not used.

When a vein is difficult to find

A vein that can be seen is not automatically suitable for venipuncture. Site selection also depends on the vessel’s direction, size, depth, stability, surrounding anatomy and the condition of the skin. Palpation remains important because it helps the collector assess characteristics that a surface image cannot fully show.

Near-infrared vein visualisation can make superficial subcutaneous vessels easier to see, particularly when ordinary visual assessment is difficult. It is an adjunct to clinical assessment, not confirmation that a displayed vessel is safe or suitable for puncture. The FDA summary for one cleared vein locator states that the device supplements line-of-sight visualisation and does not replace conventional methods used by qualified professionals. A product that reports estimated vein depth also needs device-specific evidence for its measurement range, accuracy and intended use.

The WHO phlebotomy guideline and the current CLSI PRE02 standard provide broader guidance on venous site selection and collection practice. Product-specific claims for any vein visualisation system should be checked against its instructions for use and technical documentation.

2. Capillary blood collection

Capillary blood collection, also called skin-puncture or peripheral blood collection in some markets, uses a controlled puncture or incision to obtain a small sample from superficial vessels.

The specimen is not drawn from one isolated capillary. It contains an indeterminate mixture of blood from arterioles, venules and capillaries, with possible contributions from interstitial and intracellular fluid. This definition appears in China’s current WS/T 848-2025 guideline for capillary blood specimen collection. Technique therefore has a direct effect on sample quality.

Capillary collection is useful when only a small volume is required, venous access is difficult, testing takes place near the patient, or a decentralised collection programme has validated the full workflow.

Common uses of capillary blood

Depending on the device and validated test method, capillary samples may be used for:

blood glucose testing;
selected point-of-care tests;
haemoglobin and selected haematology measurements;
HbA1c testing;
newborn screening;
dried blood spot testing;
selected clinical chemistry and immunoassay tests;
paediatric and difficult-access sampling;
remote studies and decentralised diagnostic programmes.

Capillary and venous specimens are not automatically interchangeable. Collection site, matrix, tissue-fluid contamination, haemolysis and analyte physiology can all affect results. WS/T 225-2024 also notes that capillary and venous serum are interchangeable only for some clinical chemistry items.

A 2025 study reported equivalent results for selected analytes using specific miniaturised assays and novel capillary collection methods. Those findings apply to the systems and analytes evaluated in that study. They do not establish interchangeability for every capillary device, assay or laboratory workflow. See the study in The Journal of Applied Laboratory Medicine.

Three important capillary blood collection approaches

Fingerstick, upper-arm assisted collection and neonatal heelstick represent three important conventional and emerging pathways. They are not an exhaustive or universal official classification of every possible capillary site or device.

A. Fingerstick capillary blood collection

Fingerstick is the most familiar capillary sampling approach for adults and older children. A sterile lancet creates a controlled puncture at an appropriate part of the finger. The blood may then be:

applied directly to a test strip or point-of-care cartridge;
collected into a capillary or transfer tube;
collected into a microcollection container;
applied to an approved dried-sample device.

Fingerstick is closely associated with glucose testing, but it can support other tests when the required volume, collection procedure and analytical system are validated for capillary blood.

Lancets used for fingerstick collection

A single-use safety lancet has an integral mechanism that shields the sharp and prevents reuse after activation. In assisted blood glucose monitoring, the US Centers for Disease Control and Prevention recommends single-use, auto-disabling fingerstick devices and disposal in an approved sharps container at the point of use.

Safety lancets may differ by:

contact, pressure, top-button or side-button activation;
needle or blade construction;
fixed or adjustable penetration depth;
intended sample volume;
intended professional or lay user.

Gauge and penetration depth matter, but they do not determine blood volume or discomfort on their own. Device design, puncture site, skin characteristics and sampling technique also contribute.

For commercially available examples, see LINKFAR’s safety lancet product category. Product examples include Safety Lancets – PA with needle- and blade-type options, Safety Lancets – PA2 with fixed gauge and depth variants, Safety Lancets – APA with adjustable penetration depth, and Safety Lancets – TPA with one-step activation.

Single-use safety lancets should be distinguished from a reusable lancing-device workflow. LINKFAR’s blood lancets are intended for use with compatible lancing devices, while the Precise Adjustable Lancing Device supports capillary blood collection with disposable peripheral blood lancets. Product instructions determine compatibility, cleaning, intended user and whether a device is suitable for professional or personal use.

B. Upper-arm vacuum-assisted capillary blood collection

Upper-arm capillary collection is an emerging option for selected decentralised, remote, research or laboratory workflows. Terms used for this category include vacuum-assisted capillary collection, on-body blood collection and arm-based capillary microsampling.

Depending on the product, an attached device uses a lancet, blade or microneedle structure to create a controlled skin opening. Vacuum assistance then helps blood flow into an integrated or compatible microcollection tube.

These systems are designed to collect a liquid microvolume away from the fingertip and transfer it into a container for handling or transport. Suitability remains specific to the device, specimen matrix, analyte, transport conditions and analytical method.

The FDA’s 510(k) summary for Tasso+, for example, describes a single-use device intended to obtain microlitre capillary whole-blood samples. Its mechanism creates an incision and applies a slight vacuum to assist flow into a collection tube. This is one example of the category, not evidence of universal performance for all upper-arm devices or tests.

The collection site and vacuum assistance do not turn the specimen into venous blood. An upper-arm device described for capillary collection still produces a capillary specimen. The receiving tube, additive, minimum fill, mixing procedure and analytical system must all be suitable for that specimen and volume.

C. Neonatal heelstick blood collection

Heelstick is a specialised capillary sampling approach for newborns, premature infants and young infants when clinically appropriate. A device selected for the infant’s age, weight, tissue depth and required volume creates a puncture or controlled incision in an approved part of the heel.

Common applications include:

newborn screening;
dried blood spot cards;
selected glucose, bilirubin, blood gas or haematology testing;
other small-volume tests specified by the clinical team and laboratory.

Neonatal heel devices may use a needle puncture or a controlled blade incision. They are not simply larger versions of adult fingerstick lancets. Incision depth, width, motion and placement must fit neonatal anatomy and the required specimen.

LINKFAR’s neonatal heel blade safety lancet category includes Heel Blade Safety Lancets intended for heel-stick capillary specimen collection in newborn and premature-infant workflows. Device size and technique must still be selected according to the infant, the required specimen and the applicable instructions for use.

The WHO capillary sampling guidance identifies the medial or lateral plantar surface as the general heel-prick area and warns against unsuitable sites and excessive depth. Exact device selection and technique must follow the current institutional procedure and the manufacturer’s instructions for use.

Fingerstick vs upper-arm vs neonatal heelstick

Capillary approach	Typical population or setting	Collection technology	Typical sample handling	Important qualification
Fingerstick	Adults, older children, point-of-care testing and selected self-testing	Needle or blade lancet, often a single-use safety lancet in professional settings	Direct-to-test application, capillary tube or microcollection container	Test and device must be suitable for capillary blood and the intended user
Upper-arm assisted collection	Selected decentralised, remote, research or laboratory workflows	Attached on-body device with a small incision or microneedle structure and vacuum assistance	Usually a liquid microvolume collected into a compatible tube	Performance is specific to the device, matrix and analyte
Neonatal heelstick	Newborns, premature infants and young infants	Specialised heel puncture or incision device	Microcollection container, capillary tube or dried blood spot card	Requires age-, weight-, site- and depth-appropriate selection and trained technique

Less common capillary collection sites may be used in specific validated applications. The earlobe, for example, has been used in some screening or research settings. It should not be presented as a routine alternative without a defined procedure and validated test system.

3. Arterial blood collection

Arterial blood collection, also called arterial blood sampling, obtains blood directly from an artery, most often the radial artery. Its main purpose is to evaluate gas exchange and acid-base status.

Common uses of arterial blood

Arterial specimens may be used for:

arterial oxygen partial pressure;
arterial carbon dioxide partial pressure;
blood pH and bicarbonate-related assessment;
evaluation of respiratory failure;
assessment of oxygen therapy or ventilatory support;
selected critical-care measurements, including lactate and electrolytes where specified.

The sample is usually collected into a purpose-designed heparinised blood-gas syringe. Air exposure, delays, anticoagulant balance and transport conditions can materially affect the result, so handling must be rapid and controlled. MedlinePlus describes the radial artery as the most common collection site for blood-gas testing, while also noting that other arteries may be used.

Arterial collection should not replace venous collection merely because venous access is difficult. The specimens have different physiological characteristics and serve different diagnostic purposes.

Venous vs capillary vs arterial blood: which method fits which need?

Question	Venous blood	Capillary blood	Arterial blood
Best suited to	Broad routine laboratory testing	Microvolume, point-of-care, paediatric and validated decentralised testing	Blood gases and acid-base assessment
Available volume	Moderate to large	Small to microvolume	Small and purpose-specific
Typical collection site	Arm vein	Finger, neonatal heel or an approved alternative site such as the upper arm	Usually radial artery
Common collector	Trained healthcare professional	Healthcare professional; self-collection only where the device and test permit it	Specially trained healthcare professional
Common sample matrices	Whole blood, plasma or serum	Whole blood, capillary plasma or serum after validated processing, or a dried specimen	Heparinised whole blood for blood-gas analysis
Can it replace the other methods?	Not universally	Not universally	Not for routine substitution

Selection principle: The appropriate method is the one that produces a suitable specimen for the ordered test while protecting the patient, collector and sample quality. No method is universally best.

Why microcollection tubes matter in low-volume testing

A microcollection tube describes a small-volume container. It does not, by itself, identify where the blood came from. This distinction is important because four separate questions are often compressed into the phrase “micro blood collection”:

Workflow question	What needs to be defined
Blood source	Venous, capillary or arterial
Specimen matrix	Whole blood, plasma, serum or a dried specimen
Container	Tube volume, additive, closure, minimum fill and mixing requirements
Testing pathway	Point-of-care testing, local laboratory analysis or transport to a remote laboratory

Many microcollection tubes are designed for blood obtained directly by fingerstick, heelstick or another approved capillary site. In other validated workflows, a small venous specimen or an approved aliquot may be placed into a low-volume container. The permitted source and transfer method must come from the tube instructions, the analytical system and the laboratory procedure. Transferring blood between containers can change the additive ratio, damage cells or introduce contamination if the workflow was not designed for it.

Lower sample-volume requirements in some point-of-care and miniaturised laboratory tests make microcollection more relevant. A validated low-volume workflow may reduce the amount of blood collected and can provide an alternative to a standard evacuated tube for a defined test. It does not follow that a microcollection tube can replace an evacuated venous tube for every analyser, analyte or patient.

Remote and home collection add another requirement: the sample has to remain suitable until it reaches the testing site. The complete system must account for collection technique, tube additive, fill volume, closure, leakage, stability, time and temperature, packaging, transport and processing on arrival. A container that can hold and ship a small blood sample is not automatically compatible with the intended test.

CLSI GP42 covers capillary collection devices and microcollection containers. The practical decision still rests on the applicable product instructions and validation of the full collection-to-result workflow.

Whole blood, plasma, serum and dried blood are not the same

Collection route and specimen matrix are separate decisions.

Whole blood

Whole blood retains the blood cells and liquid components. It is commonly required for haematology, HbA1c and selected point-of-care tests. An appropriate anticoagulant may be required.

Plasma

Plasma is the liquid portion obtained after anticoagulated blood is centrifuged. The intended test determines the anticoagulant and required blood-to-additive ratio.

Serum

Serum is obtained after blood is allowed to clot and the specimen is centrifuged. It differs from plasma in its clotting components and is widely used in chemistry, immunology and serology.

Dried blood spots

A dried blood spot is a sample format, not a fourth anatomical blood source. Blood, often obtained by fingerstick or heelstick, is applied to an approved card or device and dried under defined conditions. Suitability depends on the assay, spot quality, drying, storage and transport requirements.

Where do blood cultures and catheter draws fit?

Some common search terms describe a special workflow rather than a separate blood source.

Blood culture collection

Blood culture collection is designed to detect bacteria or fungi in the bloodstream. It is generally a specialised venous collection procedure with strict requirements for skin antisepsis, bottle selection, collection volume, timing and contamination control.

Collection from vascular access devices

Blood may sometimes be collected from an existing venous or arterial catheter. This is an access route within venous or arterial sampling, not a new specimen category. Institutional procedures must address dead-space blood, infusions, contamination and line-specific risks.

How collection method affects test results

Venous, capillary and arterial specimens reflect different physiological conditions and are collected through different processes. Results may be affected by:

blood source and collection site;
specimen matrix;
patient posture, fasting, exercise and collection time;
oxygen therapy or medication timing;
tourniquet duration;
tissue-fluid contamination;
excessive squeezing of a finger or heel;
haemolysis, clotting or underfilling;
contact with air;
an incorrect additive or blood-to-additive ratio;
transport time and temperature;
delayed separation of cells from serum or plasma.

A reference interval or clinical interpretation established for one specimen type should not be assumed to apply when another specimen type is used.

Core principles for reliable blood specimen collection

Regardless of collection route, a reliable process should include:

correct patient identification;
confirmation of test-specific patient preparation;
selection of the correct collection route and site;
use of a sterile, compatible, single-use sharp where applicable;
selection of the correct tube, additive and fill volume;
prevention of contamination, haemolysis and clotting;
immediate and accurate specimen labelling;
correct collection order, timing, storage and transport;
safe disposal of used sharps at the point of use;
adherence to the device instructions, laboratory requirements and local clinical procedure.

The CLSI GP42 standard provides detailed procedures for capillary collection sites, puncture depth and disposable collection devices. Local requirements and the applicable device instructions still govern the actual procedure.

Frequently asked questions

What are the three main methods of blood sample collection?

The three principal routes are venous blood collection, capillary blood collection and arterial blood collection. Arterial blood collection is also commonly called arterial blood sampling. The three routes provide different volumes and physiological information, so they are not universally interchangeable.

What is the most common blood collection method?

Venous blood collection is the most widely used route for routine laboratory testing because it can provide enough blood for many tests and specimen types.

When is capillary blood collection used?

Capillary collection is used when only a small volume is needed, in many point-of-care applications, for selected paediatric and neonatal tests, and in validated decentralised or remote workflows.

What are the main capillary blood collection approaches?

Important approaches include fingerstick, neonatal heelstick and newer upper-arm assisted or on-body collection. These terms describe different sites and technologies, not one universal official classification.

Is upper-arm vacuum-assisted blood collection capillary or venous?

The FDA-cleared Tasso+ device is intended to collect microlitre capillary whole-blood samples from the upper arm. Other devices must be assessed according to their own intended use and instructions.

Is a microcollection tube only used for capillary blood?

Not necessarily. “Microcollection tube” describes the container and its low-volume role, not an anatomical blood source. Many are intended for capillary collection, while some validated workflows may use a small venous specimen or approved aliquot. Follow the tube instructions and laboratory procedure.

Can a microcollection tube replace a standard evacuated tube?

Only for a defined and validated workflow. The specimen source, additive, fill volume, analyser, test method and handling requirements must all be compatible. A low-volume tube is not a universal substitute for an evacuated venous tube.

Can an upper-arm or home-collected sample be sent to a laboratory?

Yes, when the collection system and test workflow are designed and validated for transport. Sample stability, packaging, time, temperature, leakage control and laboratory processing must be specified. Collection at home does not, by itself, establish that a sample is suitable for mailing or analysis.

Is capillary blood the same as venous blood?

No. Capillary specimens are obtained through a skin puncture and contain blood from small vessels with possible tissue-fluid contributions. Some measurements may be comparable after validation, but the specimen types are not automatically interchangeable for every analyte.

Is a dried blood spot a blood collection method?

It is more accurately described as a specimen format and collection workflow. The blood is usually obtained by fingerstick or heelstick and then applied to an approved card or device.

What is the difference between a safety lancet and a neonatal heel lancet?

A safety lancet is a broad category of single-use capillary puncture devices with an integral sharps-protection mechanism. A neonatal heel lancet is designed specifically for heel sampling and may use a controlled needle puncture or blade incision suited to neonatal anatomy and the required volume.

Can the same device be used for every capillary test?

No. Selection depends on the intended user, collection site, required volume, patient characteristics, specimen container and validated analytical workflow.

Who decides which blood collection method should be used?

The ordered test, laboratory requirements, clinical procedure and the collection device’s instructions determine the method. Patients and untrained users should not substitute one route or device for another without appropriate professional guidance.

Capillary blood collection solutions from LINKFAR

LINKFAR’s portfolio includes safety lancets, neonatal heel blade safety lancets, blood lancets and lancing devices. These products support different parts of the capillary sampling workflow, but the correct device still depends on the intended user, patient population, required sample and applicable product labelling.

Explore the full capillary blood collection product category.
Compare LINKFAR safety lancets.
Review neonatal heel blade safety lancets.
Browse blood lancets and lancing devices.

Product availability, intended users and regulatory status may vary by product and market. Always consult the applicable product labelling and instructions for use.

Get a quote

Contact LINKFAR for product-specific information, technical documentation, distribution enquiries or quotation support.

Contact the LINKFAR team

References

World Health Organization. WHO Guidelines on Drawing Blood: Best Practices in Phlebotomy. 2010.
Clinical and Laboratory Standards Institute. GP42, Collection of Capillary Blood Specimens, 7th Edition. 2020.
National Health Commission of the People’s Republic of China. WS/T 225-2024: Collection and Processing of Blood Specimens for Clinical Chemistry. 2024.
National Health Commission of the People’s Republic of China. WS/T 848-2025: Guidelines for Collection of Capillary Blood Specimen. Published 2025; effective 2026.
US Food and Drug Administration. 510(k) Summary K221131: Tasso+. 2022.
DiPasquale C, et al. Equivalence between Capillary Blood and Venous Blood Test Results Using Miniaturized Assays and Novel Collection Methods to Support Routine Bloodwork. The Journal of Applied Laboratory Medicine. 2025;10(5):1090-1104.
Centers for Disease Control and Prevention. Considerations for Blood Glucose Monitoring and Insulin Administration. Accessed 12 August 2026.
MedlinePlus. Blood Gases. Accessed 12 August 2026.
Clinical and Laboratory Standards Institute. PRE02, Collection of Diagnostic Venous Blood Specimens, 8th Edition. 2025.
US Food and Drug Administration. 510(k) Summary K101838: Vein Locator, VTS1000. 2010.