How Can Adult British Citizens Born Outside the UK Get A National Insurance Number?

If your children have never lived in the UK they won't get a National Insurance number unless they do. If they ever come to live in the UK and you claim Child Benefit for them they will get a number shortly before their 16th birthday. If they are already over the age of 16 when they arrive they will need to apply for a number. In those circumstances you need to contact your local Jobcentre and they will arrange an appointment.

I gather THEY are British citizens? You registered them etc....? Do NOT need such a number, if not resident! @ Big H? Nasty! How do you know the kids are not British AND citizens of wherever? Also DO NOT presume all "incomers" are on the scrounge! My other half had a NI number and worked many, many years BEFORE eventually becoming a British citizen; a 100 times better citizen than I have ever been, and making a valuable contribution to our country !!! You need your number to work legally with ILR for example, regardless if a citizen or not. It is NOT in the welcome pack at the Town Hall ceremony!