Rare Blood Program

Did you know that some people’s blood is rarer than others? It’s not just about being type A, B, O or AB. On the surface of our red blood cells are proteins called antigens. There are more than 600 known antigens — and some combinations of antigens are far less common than others.

Whenever a blood transfusion is required, time is of the essence. But if someone in need has rare blood, finding a matching donor can be hard. Through our Rare Blood Program, we make sure lifesaving rare blood is available to patients whenever and wherever it’s needed. 

To deliver on that promise, we need everyone with rare blood to donate regularly.

View and print the brochure "How rare is your blood"

Rare blood FAQs


How do I donate rare blood?

To see if you have lifesaving rare blood in you to give, contact us at 1 888 2 DONATE (1-888-236-6283) and we’ll arrange for the best testing method for you. Rare blood donors can give blood every eight to 12 weeks — but may also be called upon as needed if their specific rare blood type is urgently required.

How do I get tested to see if I have rare blood?

Preliminary testing for rare antigens can be done on a blood donation, through blood samples or by a buccal swab sample that you mail in to us. Contact us at 1 888 2 DONATE (1-888-236-6283) and we’ll discuss your options and arrange for the best testing method for you.

How will I find out about my test results?

We’ll let you know about your rare blood status by phone or mail. If your testing was done through a blood sample or buccal swab, confirmation testing will be completed on your first donation.

If I have rare blood, do my siblings also have rare blood?

Since blood types are inherited, there’s a one-in-four chance your brothers and sisters will have the same rare blood type as you. If you know your blood type is rare, we encourage you to speak with your siblings and ask them to consider becoming a rare blood donor by contacting us at 1 888 2 DONATE (1-888-236-6283) to arrange for testing.

How often can I donate?

You can give blood every eight to 12 weeks. We depend on our rare donors to give blood regularly and be available in times of need. When a specific rare blood type is in urgent need, and supplies have been depleted, we will call our rare donors to ask them to donate right away. If we call you, it means your blood is needed immediately or our inventory of your specific type has fallen below optimal levels.

What if I cannot donate when asked?

There are many reasons why you may not be able to donate when asked. We understand that it’s not always possible to donate — but would ask you to do so as you are able.

What if my test results show I don’t have rare blood?

Even if you don’t have rare blood, we still encourage you to donate whole blood. Remember, every donation is valuable and can save lives. Call us at 1 888 2 DONATE (1-888-236-6283) to book an appointment to donate.

Should I tell my doctor I have rare blood?

Yes. Information about your rare blood type is important in some medical situations — if you ever need a blood transfusion or during pregnancy, for example. We can provide a letter explaining your rare type that you can take to your doctor.

Will my privacy be protected if I become a rare blood donor?

If you decide to participate in our Rare Blood Program, we’ll need to collect and use some personal information about you. That personal information is not shared with the International Rare Donor Panel (IRDP). We provide just the details about your rare blood type to the IRDP.