How do I find out whether someone is still living or has died?

They moved to St Catherine's House in 1970.

They haven't been there for many years either.

I'm not sure that there is still anywhere you can go and look at the actual index volumes.

It depends on the lengths you want to go to and how badly you need to know if they died.
You know the house was sold 18 months ago. Could you knock on the door and say to the current owners that you're very sorry to bother them but you are looking for the previous occupants, do they know the circumstances on how the house was sold?
They will know details of the chain, so if the person was deceased when it was sold, or was going into care.
You could also try ringing round care homes in the area, and saying you want to see how your - make something up, your dad/mum whatever - is doing and give them the name see if they start telling you. If not, you simply say you have the wrong name and hang up.
If all internet searches are bringing nothing up, you're just going to have to do a little old fashioned snooping.
This is all PIs will do

It can be really difficult sometimes, I tried everything to see if a family member had died (they’d been missing for a number of years). I tried Facebook, google, Salvation Army but in the end I found she’d died by searching death certificates online. It took a little while but I managed to narrow my search down, then ordered the certificate. I rang up the place of death and spoke to a few people so managed to find out the hospice where they’d died and place they were buried.

Break the search down into parts. First, I’d find their DOB. Use FreeBMD for this or the relevant OPC (parish) records if you know where they were born. Having found that, search on the GRO site for their death. You can also use FreeBMD to see if they married and, by cross-referencing, find their spouse. Searching for their spouse might give you information.

You can also search local papers’ funeral notices and Findagrave, aswell as 192.com. You can sometimes see who they lived with on 192 without an account.

Knowing their first and last name and their address until fairly recent then 192.com is a good start point (especially if you know who else was in the house) as that may give you middle initials if they have any.

Which with the decade they were born would let you find a birth to get a more accurate age.

If their adult children lived with them at that address at any point it would also give you names to look up as well.

They moved to St Catherine's House in 1970.

This.

You can search the indexes.

Ancestry don't have recent deaths. The GRO is your best option. Followed by electoral role.

I have tracked someone down for a friend before. Friend could only remember her first name and thought she knew her married surname but I couldn't get anything from it.

She eventually found an old letter with an old address on from 30 years ago. I was able to narrow down options from the address using historic electoral role info from Ancestry. A woman with the married name friend has thought, was living in the same area but had moved not far away.

The electoral role helped me confirm because of who else was registered at the address and because I'd managed to confirm her age using info from Ancestry.

Do the adult children have any Facebook presence? Most people's privacy settings prevent searching through posts or comments too much, but you might find a reference to the person especially if they've died, commiserations or that kind of thing. That would at least give you a rough date. I agree that it's easier in Ireland, I was lucky enough to find a very detailed community newsletter on Facebook which helped me trace someone.

Just about all deaths are registered in the UK as you can't bury or cremate someone until that is done. Also if you want to get their finances sorted, you need the death certificate.
So hopefully you will find out the information you need soon enough.

looking for children or grandchildren on social media can be very good.

I tracked down when my ex (father of my two daughters) arrived back in the UK thanks to some very slack privacy settings of a relative of his who uploaded hundreds of pics from a family party.

If you come at something like this from different angles you can usually find someone. Various posters have made suggestions. Work through them all and you will turn things up. It can be good to bounce ideas off others who know what is going on (not suggesting you do that here as you clearly want to keep this confidential). Sometimes you don't spot a lead. Tracking known associates and relatives can turn things up.

A friend does finding people as part of her work. She has had more recent successes using facial recognition (for instance PimEyes) that has surprised me.

Give them a sharp prod

If they have a middle name/names then searching for their birth may help you narrow down their age, which may then help you trace a death.

searching 192.com to try and get an idea of their most recent location (if they are listed) is helpful as well.

a lot also depends on the name. Finding a John James Smith is much much harder than a Trixibelle Nightingale Davies Smith.

100% this!!!!

On the off chance they are of Irish heritage you could try RIP.ie. The vast majority of Irish families post death notices and funeral arrangements there, and this often includes 1st/2nd generation living abroad at the time of death. Eg ‘the death has occurred of XXX of Manchester, formerly of Killarney’

This is why the UK needs an equivalent of rip.ie

When did you last know this person was alive? https://www.freebmd.org.uk/ has death records up to 1997.
The General Register Office (GRO) publishes records up to 6 months before the day you're searching https://www.gov.uk/research-family-history

Try a library near you, librarians can be very good, usually they have free access to Ancestry. The GRO website lists some larger libraries that hold microfiche copies of GRO index numbers, which you'd need if you want to request the actual death certificate.

Am sorry, my brother sorted it out so don't know the exact cost. We had to find the missing brother for his share of late fathers estate. I don't think it was more than £2-300 though, and they found him in less than two weeks. This was 5 years ago.

Missing brother wasn't working and wasn't registered to vote or with a GP, so it was hard on my own trying to find. I tried the local housing dept too, to pass on a message and they lied and said he wasn't on their books. Hit a dead end, that's why did a PI.

Good luck. I don't think all PI's use legal methods tbh....!

May I ask you how much this cost please? I’m trying to track down my DD’s father who is proving completely untraceable and I’m pretty skilled at researching. Tried every method suggested here, many many millions of times.

Other possible things to try:

If they have been a company director you can look them up by name on Companies House.

If they have been a trustee of a charity that is regulated by the Charity Commission, you can look them up by name on the Charity Commission website.

You may be able to find their date of birth via an ancestry search on their full name and place of birth. Once you have a date of birth - even if it's roughly within five years - it's easier then to search for them online, including for a possible death.

Ancestry does also pull more recent death information from funeral-notices.co.uk, or you can consult the latter directly. I think it has information currently up to 2022.

I assume from what you have put that you are in the UK. Always ponder whether someone has died elsewhere as they are then missed, unless there is something will-related in the UK too.

Two of your friends are probate records and the electoral roll. With probate it depends when and which bit of the UK.

Search probate records for documents and wills (England and Wales) - GOV.UK

Electoral roll? Voters can tick to not be included in what is called the Open Register. If they are in the Open Register the 2026 roll is on 192.com (and elsewhere).

Electoral Roll - Electoral Register - 192.com

So coming up on the electoral roll is a good indicator of probable life.

192 is good for lots of things too, but you will need to pay something for searches. You can often build a trail of where someone might have been in recent years.

Could they have died abroad? My late dad did tracing research often for inheritance issues. I remember him saying it was difficult ( but not impossible) if people had moved abroad. He tracked an elderly Irishman to America for a farm inheritance job. Sorry I’m not being much help- can’t ask him how he did it 😔