Written and maintained by CASRAI Editorial Board
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This page describes products and general use; it is not medical advice. Follow your facility’s protocol and the instructions for use of the tubes you stock.
People searching for blood draw tube colors usually need to match a closure colour to its additive, and to know which tube comes first when several are collected in one venipuncture. The closure colour codes the additive inside the tube. The chart below uses the closure colours listed in the CLSI summary of GP41 (Collection of Diagnostic Venous Blood Specimens) and the cap colours printed on the Greiner Bio-One VACUETTE order-of-draw poster. Closure colours vary by manufacturer, which is why CLSI lists a range for each additive class rather than one colour.
Blood collection tube color chart (in order of draw)
| Order | Tube / additive class | Closure colours listed by CLSI | Additive | Greiner VACUETTE cap colour |
|---|---|---|---|---|
| 1 | Blood culture tube or bottle | Not specified | Not specified | Blood culture |
| 2 | Sodium citrate (coagulation) | Blue | Sodium citrate | Blue |
| 3 | Serum tubes | Red, red-speckled, gold | Clot activator and/or gel, or none | Red or gold (serum clot activator) |
| 4 | Heparin | Dark green, light green, speckled green | Heparin, with or without gel | Green |
| 5 | EDTA | Lavender, pearl, pink | EDTA, with or without gel separator | Pink or lavender |
| 6 | Glycolytic inhibitor | Gray | Sodium fluoride / potassium oxalate | Grey |
Sources: CLSI, “Order of Blood Draw Tubes and Additives” (blog, 19 March 2019, checked 30 October 2026); Greiner Bio-One, VACUETTE Blood Collection Tubes “Best Practices” poster L2243001RN (checked 30 October 2026). Check your product’s labelling: the closure colour and additive printed on your own tubes and the manufacturer’s instructions for use are the authority for that product.
How to read the chart
Read each row as an additive class, not a single colour. CLSI gives three closure colours for heparin and for EDTA and three for serum tubes, so a green, pearl or gold closure is still identified by the additive and the label. The order column is the order of draw: CLSI states that blood must be drawn in a specific order to avoid cross-contamination of the sample by additives from different tubes, and that the order is the same for specimens collected by syringe, tube holder, or into tubes pre-evacuated at the time of collection.
The order of draw matters because of additive carryover. Greiner’s poster says that following the proper order when collecting multiple specimens in a single venipuncture helps to avoid possible test result error due to additive carryover, and that tubes should be collected according to the order established in CLSI GP41 (7th edition, 2017) or according to facility policy.
Color tubes for blood draw in order
The order is: blood culture, sodium citrate (blue), serum (red, red-speckled, gold), heparin (greens), EDTA (lavender, pearl, pink), then the gray glycolytic-inhibitor tube. CLSI adds two points. Tubes not on its list should be placed with regard to whether their additive could alter results in the next tube if carryover occurred. And plastic serum tubes containing a clot activator may interfere with coagulation testing, so only blood culture tubes, glass non-additive serum tubes, or plastic serum tubes without a clot activator may be collected before the coagulation tube.
Fill marks, ratios and ring codes (information the colour does not tell you)
- Citrate tubes use a 9:1 blood-to-additive ratio. On Greiner coagulation tubes a black arrow marks the +/-10% of blood volume needed for a properly filled sample; on all other tube types a black square is the fill mark. See the blue top tube additive guide for the citrate tube in detail.
- Coloured rings: on VACUETTE tubes, coloured rings identify the draw volume, or indicate gel, sodium heparin or blood bank use, so the ring is a second code alongside the cap.
Equivalence notes: Vacutainer, Vacuette and other brands
Vacutainer is the name of a Becton Dickinson tube range and VACUETTE is the Greiner Bio-One range; both are evacuated blood collection tubes with colour-coded closures. A “vacutainer color chart” and a “vacuette tube colors” chart therefore describe the same additive-based convention, but the exact closure shade and any ring or label markings are the manufacturer’s. Use the order of draw above regardless of brand, and the brand’s instructions for use for fill volumes. For the needle side of the system, see what is a Vacutainer needle and what is a butterfly needle.
Common mix-ups
- Red versus gold: both are listed by CLSI in the serum group; the closure alone does not say whether a gel is present, so read the label.
- Lavender versus pink: CLSI lists lavender, pearl and pink as EDTA closures, so these colours can mark the same additive class across manufacturers.
- Light green versus dark green: both are in the heparin group; whether gel is present or the heparin salt differs is shown on the label, not by the colour name.
- Colour is not the test: a closure colour identifies an additive. It does not on its own state which laboratory test the tube is for.
- Facility policy: Greiner’s poster refers to CLSI GP41 “or according to facility policy”; where your laboratory’s collection manual differs, follow it.
Frequently asked questions
What tubes are used for what blood tests?
The tube for a test is specified by the laboratory that performs it, usually in its test directory or collection manual. What the standards define is the additive class: citrate for coagulation, serum tubes, heparin, EDTA and glycolytic inhibitor, each with its closure colours in the chart above. For labelling and specimen-handling mix-ups, see specimen labeling error prevention, and for stocking the collection area, the phlebotomy lab supply checklist.
What is the color tube order for a blood draw?
Blood culture, blue (sodium citrate), red/red-speckled/gold (serum), green (heparin), lavender/pearl/pink (EDTA), gray (sodium fluoride/potassium oxalate), per CLSI.
What color tube is used for a CBC?
A CBC request names its tube in the performing laboratory’s collection instructions. If the laboratory specifies an EDTA tube, CLSI lists lavender, pearl and pink as EDTA closure colours. Confirm against the laboratory’s own guidance and the tube label.
What color tube is used for a CMP?
Likewise, the laboratory specifies the tube for a CMP. The additive classes that CLSI lists as possibilities in that part of the order are serum tubes (red, red-speckled, gold) and heparin tubes (dark green, light green, speckled green); the laboratory’s instructions decide which one applies.
Sources
- Clinical and Laboratory Standards Institute, “Order of Blood Draw Tubes and Additives”, 19 March 2019, clsi.org, checked 30 October 2026. Summarises CLSI GP41, Collection of Diagnostic Venous Blood Specimens.
- Greiner Bio-One North America, “Best Practices: VACUETTE Blood Collection Tubes, Order of Draw and Inversions”, poster L2243001RN, gbo.com, checked 30 October 2026. Cites CLSI GP41, 7th ed., 2017.
