UK Living Kidney Sharing Scheme

Since January 2012, the UK Living Kidney Sharing Scheme (UKLKSS) is the collective term used to describe the schemes in which donated kidneys are 'shared' across the UK. The UKLKSS was established after the introduction of the Human Tissue Act 2004 and the Human Tissue (Scotland) Act (2006) and has since developed into one of the most successful schemes in Europe. The UKLKSS includes transplant cycles and transplant chains initiated by non-directed altruistic donors (NDADs).

The UKLKSS include:

Transplant cycles

Some donor and recipient pairs may be unable to donate due to having incompatible Human Leucocyte Antigen types or blood groups. When this happens, they are registered in the sharing scheme to find compatible matches with another donor and recipient pair.

If an incompatible pair find a match with another pair then they can form a transplant cycle. Currently transplant cycles can be made up of:

• 2 transplant cycle - this involves 2 pairs of donors and recipients, where a donor from the 1st pair donates to the recipient of the 2nd pair which allows the donor of the 2nd pair to donate to the recipient of the 1st pair.
• 3 transplant cycle - this involves 3 pairs of donors and recipients and follows the same pattern as a 2 transplant cycle. However, as there is a 3rd donor and recipient pair, the 2nd pair donor will donate to the recipient of the 3rd pair which allows the donor in the 3rd pair to donate to the recipient of the 1st pair, completing the cycle.

Compatible donor and recipient pairs can also seek a better match by registering in the sharing scheme.

Transplant chains

When a person donates anonymously as a NDAD to a recipient on the national waiting list, they are registered into the sharing scheme to initiate a transplant chain.

The donated kidney is allocated to a recipient on the sharing scheme. This means the original donor paired with that recipient can go on to donate to another recipient on the sharing scheme or to someone on the national waiting list.

Transplant chains involve the NDAD and either 1 or 2 pairs of donors and recipients, depending on the length of the chain:

• 2 transplant chains - A NDAD donates a kidney to a recipient on the sharing scheme to initiate the chain. The donor from this pair then donates to a recipient on the national waiting list, ending the chain.
• 3 transplant chains - A NDAD donates a kidney to a recipient on the sharing scheme to initiate the chain. The original donor paired to the 1st recipient then donates to a 2nd recipient on the sharing scheme, who's donor completes the chain by donating to a recipient on the national waiting list.

If there is a high priority recipient on the national transplant list, a NDAD kidney will be offered to the priority recipient before being included in the matching run.

Living Donor Kidney Matching Run

To identify optimal transplant cycles and transplant chains we undertake matching runs 4 times per year. 

The Transplant TV video Let's talk about living kidney donation - The Living Kidney Sharing Schemes demonstrates how the schemes operate. Please note that this video uses the previous names for the two schemes - paired/pooled donation refers to the transplant cycles and altruistic donor chains refers to the transplant chains.

For more information about non-directed and directed altruistic donation, visit our website.

Important information

• Timetable for 2025 UKLKSS matching runs (PDF 480KB)
• UKLKSS quarterly performance data (PDF 117KB)
• Decision-making resources
• UK 'Organ Donation and Transplantation 2030: meeting the need' strategy