For NHS can Nominate your next of kin, you must inform the NHS trust, GP etc
All competent adult patients are asked to nominate their next of kin formally on admission to hospital. This is not simply a contact number but has potential significance, as the nominated person must be willing to best reflect what they believe would have been your wishes in the event of your incapacity or death. It is this person that staff would turn to for advice/guidance/help about your care if you were unable to respond yourself. For example, this might be because you are unconscious or unable to communicate due to illness or injury.
in the event of your death, it is your next of kin who would be consulted about bereavement issues such as making funeral arrangements, arranging a hospital post mortem or organ/tissue donation.
You are not obliged to give a next of kin, but if you don't initially, you can change your mind at any time.
What is the role of next of kin?
Your next of kin cannot consent or withhold consent for care on your behalf. But as your next of kin, their views on what you would have decided will be sought. These views will contribute to the decision that the clinicians caring for you (and who have a duty to act in your best interest) will make regarding your treatment and care. Thus, if you cannot make that decision for yourself, the final decision of care rests with the clinician in charge of your care.
If, in the case of an emergency, you have not had the opportunity to nominate anybody as your next of kin, we would prefer to seek advice from whoever we believe to be 'closest' to you and best able to reflect your wishes; for example, your current partner or closest relative.
Who can be my next of kin?
Historically, the next of kin was the spouse or nearest relative of the patient, but modern day families may have a different structure - cohabiting but unmarried, long term relationships but not cohabiting, same-sex partners etc. Your next of kin does not need to be a blood relative or spouse; they can be your long-term partner, cohabitee or even a close friend.
Whoever they are, you must ensure that the person you nominate is aware of the duty/responsibility that being next of kin may entail, e.g. they may have to make decisions on your behalf as outlined in the previous answer. You must ask them if they are willing to be nominated as your next of kin.