How Long Between Blood Donations in Japan? | Next Eligible Date Chart for 400 mL, 200 mL and Apheresis, Plus Annual Limits
After donating blood, few people can say straight away when they are allowed to give again. In Japan the wait ranges from 1 to 16 weeks depending on which type of donation you made last time and which type you want to make next, and there are also limits on how many times and how much you can give in the most recent 52 weeks. Based on the Japanese Red Cross Society's donation criteria, this guide gives a chart of the next eligible date for each previous donation type, worked examples with real dates, how the 52-week limits work, how apheresis donations are counted, the age, weight and haemoglobin requirements, and the reasons you may be turned away on the day even when the interval has passed.
The short answer: the next date depends on “last type × next type”
The interval between donations is set by the combination of what you donated last time and what you want to donate next. The intervals in the Japanese Red Cross Society's criteria (set by the enforcement regulations of Japan's Act on Securing a Stable Supply of Safe Blood Products) are summarised below. The figures are weeks counted from the day of the donation.
| Last donation | Next: 400 mL or 200 mL (whole blood) | Next: plasma or platelets (apheresis) |
|---|---|---|
| 200 mL whole blood | 4 weeks later (men and women) | 4 weeks later (men and women) |
| 400 mL whole blood | 12 weeks later for men, 16 weeks for women | 8 weeks later (men and women) |
| Plasma apheresis | 2 weeks later (men and women) | 2 weeks later (men and women) |
| Platelet apheresis | 2 weeks later (men and women) | 2 weeks later (platelets only 1 week after a platelet donation without plasma) |
Every interval is a whole number of weeks, so your next eligible day always falls on the same day of the week as your last donation. If you donated on a Sunday, you can donate again from a Sunday. For example, after a 400 mL donation on Sunday 1 November 2026, men can give whole blood again from Sunday 24 January 2027 and women from Sunday 21 February 2027, while both can give apheresis from Sunday 27 December 2026.
The rule for each type, and why the intervals are this long
The intervals are based on how long the body takes to replace what it has lost. The volume of blood itself (mostly water) recovers within days, but red blood cells and the iron needed to make them take much longer. That is why the wait is longest after whole blood donation, which removes the most red cells, and especially after 400 mL.
- After 200 mL whole blood: any type from 4 weeks later. Because less is taken, this is the shortest interval for whole blood.
- After 400 mL whole blood: whole blood again after 12 weeks for men and 16 weeks for women. Twice as many red cells are removed as with 200 mL, so you wait longer for red cells and iron to recover. Apheresis is possible after 8 weeks for both.
- After plasma apheresis: any type from 2 weeks later. Apheresis collects only plasma or platelets and returns the red cells to your body, so the strain is lower and the interval shorter.
- After platelet apheresis: any type from 2 weeks later. After a platelet donation that collects no plasma, however, another platelet donation is possible after 1 week.
- After 4 platelet donations within 4 weeks: wait at least 4 weeks before the next donation.
Only women have the longer 16-week wait after 400 mL because women generally have a smaller blood volume, and many have lower iron stores because of menstruation. Even when the same 400 mL is taken, recovery is considered to take longer.
If an earlier donation is still within its interval, your next date is the first day that satisfies the intervals from all of your donations. Suppose a man gave 400 mL on 1 November and then plasma 8 weeks later on 27 December. Going only by the plasma donation, whole blood would seem possible 2 weeks later on 10 January 2027, but the 12 weeks from the 400 mL donation have not yet passed, so whole blood is possible from 24 January 2027. Apheresis is possible from 10 January.
Worked example: last donation on Sunday 1 November
Taking the last donation as Sunday 1 November 2026, here is the next eligible date for each type of previous donation. These dates assume no other donations in the last 52 weeks, so no annual limit applies.
| Last donation (1 November) | Sex | Next 400 mL or 200 mL | Next plasma or platelets |
|---|---|---|---|
| 400 mL | Men | Sun 24 January 2027 (12 weeks) | Sun 27 December 2026 (8 weeks) |
| 400 mL | Women | Sun 21 February 2027 (16 weeks) | Sun 27 December 2026 (8 weeks) |
| 200 mL | Both | Sun 29 November 2026 (4 weeks) | Sun 29 November 2026 (4 weeks) |
| Plasma | Both | Sun 15 November 2026 (2 weeks) | Sun 15 November 2026 (2 weeks) |
| Platelets (with plasma) | Both | Sun 15 November 2026 (2 weeks) | Sun 15 November 2026 (2 weeks) |
| Platelets (without plasma) | Both | Sun 15 November 2026 (2 weeks) | Platelets on Sun 8 November 2026 (1 week); plasma on 15 November |
After a 400 mL donation, apheresis comes round sooner than whole blood: 4 weeks sooner for men and 8 weeks sooner for women. If you want to help again with as short a gap as possible, making your next donation after 400 mL an apheresis donation is one option. Remember, though, that apheresis has its own 2-week interval, and the 12 or 16 weeks from the 400 mL donation keep counting at the same time.
How many times and how much you can donate in 52 weeks
Separately from the intervals, there are limits on how often and how much you can donate in a year. Here a year does not mean the calendar year from January to December but the most recent 52 weeks (364 days) counted back from the day you want to donate. What matters is how much you have already given in the 52 weeks that include your intended donation day.
| Limit | Men | Women |
|---|---|---|
| Whole blood donations (200 mL and 400 mL) | Up to 6 | Up to 4 |
| Of which 400 mL | Up to 3 | Up to 2 |
| Total whole blood volume | Up to 1,200 mL | Up to 800 mL |
| Apheresis donations (1 platelet donation = 2) | Up to 24 | Up to 24 |
The limit people hit most easily is total volume. Three 400 mL donations by a man make 1,200 mL, and two by a woman make 800 mL, and either way the whole blood limit is reached at that point. After that even 200 mL is not possible, and no whole blood can be given until the oldest donation drops out of the 52-week window.
| Case (2026) | Donation dates | Next whole blood date | Limit reached |
|---|---|---|---|
| Man, 400 mL every 12 weeks | 4 January, 29 March, 21 June | 3 January 2027 | 3 × 400 mL, 1,200 mL total |
| Woman, 400 mL every 16 weeks | 4 January, 26 April | 3 January 2027 | 2 × 400 mL, 800 mL total |
| Man, 200 mL every 4 weeks | 6 times from 4 January to 24 May | 3 January 2027 | 6 whole blood donations |
| Woman, 200 mL every 4 weeks | 4 times from 4 January to 29 March | 3 January 2027 | 4 whole blood donations |
| Man, 400 + 400 + 200 + 200 mL | 4 January, 29 March, 21 June, 19 July | 3 January 2027 | 1,200 mL total |
In every case, the first donation (4 January 2026) drops out of the window exactly 52 weeks later on 3 January 2027, so the next whole blood donation is possible from that day. Going by the interval alone, the first case would seem eligible 12 weeks after 21 June, on 13 September, and the second 16 weeks after 26 April, on 23 August, but the annual limit pushes the date back by about four months.
How apheresis donations are counted: one platelet donation counts as two
The apheresis limit is 24 in the most recent 52 weeks, but each platelet donation counts as 2. That means up to 24 plasma donations on their own, up to 12 platelet donations on their own, or any mix where “plasma donations + platelet donations × 2” is 24 or less.
| Apheresis mix (last 52 weeks) | Count | Against the limit |
|---|---|---|
| Plasma only, 24 times | 24 × 1 = 24 | Exactly at the limit |
| Platelets only, 12 times | 12 × 2 = 24 | Exactly at the limit |
| Plasma 10 + platelets 7 | 10 + 14 = 24 | Exactly at the limit |
| Plasma 6 + platelets 10 | 6 + 20 = 26 | Over the limit, not allowed |
With a 2-week interval after apheresis, donating every 2 weeks for a year would give 26 donations, but the limit is 24. If you give plasma every 2 weeks from 4 January 2026, the 24th donation falls on 22 November and the next has to wait until 3 January 2027. If you give platelets every 2 weeks, you reach the limit with the 12th donation on 7 June, and the next is again 3 January 2027.
After a platelet donation that collects no plasma, another platelet donation is possible 1 week later. If you donate 4 times within 4 weeks, however, you must wait at least 4 weeks after the 4th. For example, after weekly donations on 1, 8, 15 and 22 November, the next donation is possible from 20 December, 4 weeks later.
Age, weight and haemoglobin requirements
Each type of donation has requirements for age, weight and haemoglobin concentration. Even if you meet the interval and the annual limits, you cannot make that type of donation unless you meet these.
| Type (amount) | Age | Weight | Haemoglobin |
|---|---|---|---|
| 200 mL whole blood | 16 to 69 | Men 45 kg or more, women 40 kg or more | Men 12.5 g/dL or more, women 12.0 g/dL or more |
| 400 mL whole blood | Men 17 to 69, women 18 to 69 | 50 kg or more for both | Men 13.0 g/dL or more, women 12.5 g/dL or more |
| Plasma apheresis (up to 600 mL) | 18 to 69 | Men 45 kg or more, women 40 kg or more | 12.0 g/dL or more |
| Platelet apheresis (up to 400 mL) | Men 18 to 69, women 18 to 54 | Men 45 kg or more, women 40 kg or more | 12.0 g/dL or more |
- Donors aged 65 to 69 must have donated at least once between the ages of 60 and 64. You cannot make your first donation after turning 65.
- For every type, systolic blood pressure must be 90 mmHg or higher.
- At 16 and 17 you can give 200 mL (and men can also give 400 mL from 17). Young women can give only 200 mL until they turn 18.
- If you weigh at least 45 kg (40 kg for women) but less than 50 kg, you cannot give 400 mL, but you can give 200 mL and apheresis.
- Women can no longer give platelets from age 55, but can give whole blood and plasma up to 69.
Haemoglobin is measured from a small sample taken from a fingertip or arm before donation. If you fall slightly short, you may meet the requirement when tested on another day. Since donating reduces your iron, getting iron regularly from meat, fish, soy products and green vegetables helps you keep donating.
400 mL, 200 mL and apheresis compared, and which to choose
At a donation room or blood mobile in Japan, staff will suggest the types you can give based on which blood is needed that day and your weight, haemoglobin and so on. The differences are summarised below.
| Type | What is collected | Approximate time | Main products made |
|---|---|---|---|
| 400 mL whole blood | All components of blood | About 10 to 15 minutes of collection | Red cell and plasma products |
| 200 mL whole blood | All components of blood | About 10 to 15 minutes of collection | Red cell products (mainly for small children) |
| Plasma apheresis | Plasma (red cells are returned) | About 40 to 90 minutes | Plasma and plasma-derived products |
| Platelet apheresis | Platelets and some plasma | About 40 to 90 minutes | Platelet products (for example, people undergoing cancer treatment) |
Hospitals mostly use blood from 400 mL donations. The fewer donors needed to supply one patient's transfusion, the lower the risk of side effects and infections from other people's blood, so 400 mL donation is recommended for those who qualify. Blood from 200 mL donations is mainly used for transfusions to babies and small children.
Platelets can be used for only 4 days after collection, so a steady amount has to be collected every day. That is why donation rooms take bookings for apheresis. Choosing apheresis on days when you have time and whole blood when you want to be quick, fitting the intervals to your own schedule, makes it easier to keep donating.
Why you may be turned away even when the interval has passed
The date calculated from the intervals and annual limits is only the earliest day you may donate. On the day there is an interview, a blood pressure check and a haemoglobin test after registration, and you will be asked to postpone in cases such as these.
- Your haemoglobin or blood pressure is below the requirement
- You feel unwell, have a fever, have not slept enough or have skipped a meal
- You are taking a medicine that rules out donation or requires a waiting period
- You returned from abroad within the last 4 weeks (depending on the country and timing of your stay, you may be unable to donate for longer)
- You recently had dental treatment that causes bleeding, such as an extraction or scaling
- The waiting period set for your type of vaccine has not yet passed
On donation day, sleeping well the night before, eating a meal 3 to 4 hours beforehand and drinking plenty of fluids make a vasovagal reaction (VVR), where you feel faint, less likely. After donating, rest for at least 10 minutes and avoid hard exercise, long baths and alcohol for the rest of the day.
Finding your own next eligible date with the calculator
- 1
Choose your sex
The whole blood interval after 400 mL (12 weeks for men, 16 for women) and the annual count and volume limits differ by sex, so choose this first.
- 2
Enter your last donation date and type
Enter the date and choose 400 mL, 200 mL, plasma, or platelets (with or without plasma). This alone shows the next date, weekday and days remaining for all four donation types.
- 3
Add your donations from the last 52 weeks
To check the annual limits, use “Add donation” to enter earlier donations as well. If the count, 400 mL count, total volume or apheresis count would exceed a limit, the date moves later and the reason is shown.
- 4
Enter age and weight, then add it to your calendar
Entering age and weight removes the types you do not qualify for. You can save the next date as an .ics file and add it to the calendar on your phone or computer.
When you donate, you are told your ABO and Rh blood group as part of the test results. For how blood groups combine in families, see the chart of children's blood types from their parents' blood types.
FAQ
- After a 400 mL donation, when can I donate again?
- Whole blood (400 mL or 200 mL) is possible from the same weekday 12 weeks later for men and 16 weeks later for women, and plasma or platelet apheresis from 8 weeks later for both. After 400 mL on 1 November 2026, men can give whole blood from 24 January 2027, women from 21 February 2027, and both can give apheresis from 27 December 2026.
- How many weeks should I wait after apheresis?
- After plasma or platelet apheresis, both whole blood and apheresis are possible from the same weekday 2 weeks later. After a platelet donation that collects no plasma, another platelet donation is possible 1 week later, but after 4 platelet donations within 4 weeks you must wait at least 4 weeks.
- How many times a year can I donate blood?
- In the most recent 52 weeks, whole blood up to 6 times for men and 4 for women (of which 400 mL up to 3 times for men and 2 for women), with a total whole blood volume of up to 1,200 mL for men and 800 mL for women. With 400 mL alone, men reach the volume limit after 3 donations and women after 2. Apheresis is limited to 24, with each platelet donation counted as 2.
- Does “a year” mean January to December?
- No. It means the most recent 52 weeks (364 days) counted back from the day you donate. The count does not reset at New Year; a donation on 4 January 2026, for example, keeps counting until it drops out of the window on 3 January 2027.
- Why is the interval after 400 mL longer only for women?
- Women generally have a smaller blood volume than men, and many have lower iron stores because of menstruation, so red cells and iron are considered to take longer to recover after 400 mL is taken. The whole blood interval is therefore set at 12 weeks for men and 16 weeks for women.
- What can I donate if I weigh less than 50 kg?
- 400 mL requires 50 kg or more for both men and women, so you cannot give it, but you can give 200 mL whole blood and apheresis if you weigh at least 45 kg (men) or 40 kg (women). The amount taken in plasma apheresis depends on weight: about 300 mL for women weighing 40 to under 45 kg, and 300 to 350 mL at 45 to under 50 kg.
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