You think you have hit a brick wall. You have a man in your family tree and you want to know details of his army service, but you do not know his regiment and number. You do not even have a photograph that reveals a cap badge (like the one above). Problem. Especially if he has a common name, there will be several of them, possibly hundreds. Could even be thousands if he is a John Smith, for example. So it this the end of the research road for you? Definitely not.
1. Try to find his service record anyway
Unless he continued to serve after 1922, your soldier’s service record will be in the public domain, has been digitised and is searchable via Findmypast or Ancestry, you do not need to know his regiment or number to able to carry out an effective search. It is possible to search using combinations of his name, age and where he came from. Trouble is, over half such records no longer exist at all.
Read more about researching soldier’s service records
Personally, I find Findmypast’s presentation of army service records to be the best. The indexing quality is good and leads me to more hits than Ancestry, which holds exactly the same set of records.
2. Absent Voters
Definitely your second port of call. One of the few types of record that ties together the man’s name, address, regiment and number. If he was away from home on military or naval service in mid-1918 he should be listed. Trouble is, these records have not all survived and many are not easy to access.

Read more about finding soldiers in the Absent Voters Lists
3. Pension records
If your man was awarded a disability pension (which could apply even if he was not discharged on medical grounds and had not been a casualty) his record should show his name, address, regiment and number, along with other useful details. A very valuable set of records exists and is searchable online. They can be searched by just name and/or place. Trouble is, they have been placed into the Ancestry subsidiary Fold3.

Read more about finding the pension records
4. Casualty lists
From 1917 onwards, if a man was named in an official list as wounded, missing or as a prisoner of war, the list added his place of residence or enlistment (just the town name, rather than street level). This may not get you down to an individual as it is possible that there was more than one casualty from the same place with the same name, but it does provide some “possibles” that you can work on.

Read more about researching the casualty lists
If your man was named as missing or a prisoner of war, then there is a splendid and free source of information in held by the Red Cross. They add his date of birth, address and next of kin (be careful, though, as the man did not always give accurate details and German spelling or British names and addresses can be a liitle off).

Read more about Red Cross POW records
5. Silver War Badge
This is a less helpful source but it is just possible that it will help you differentiate between “possibles” of the same name. Men discharged on medical and certain other grounds were awarded the Silver War Badge. Its issuing roll often includes their age (in years and sometimes months) at the date of discharge, as well as their regiment and number. These records are online and searchable. Trouble is, they are not searchable on age so you will need to examine each man separately.

Read more about Silver War Badge records
6. Local newspapers
More and more local newspapers are appearing online, many via the British Newspaper Archive. It is always worth trying a search using the man’s street address rather than his name. You never know what may come up, but very often it will give a valuable military clue.
7. Siblings or even father or son
If you have worked through all of that and are still stuck, it may be worth some lateral thinking. Did your soldier have a brother, father or son who would have served in the same time period? If so, it may be worth seeing if you can find their service record. When recording the name and address of next of kin, other members of the family who were serving are often mentioned along with their regiment.