Find AncestryDNA Matches with Common Ancestors

A Segment-ology TIDBIT

Disclaimer 1 – This is a search methodology, and may not zero in on your Ancestor  100% of the time.

Disclaimer 2 – This process works down to the lowest cM and any generation. There is NO guarantee that the DNA segments are linked to any Common Ancestor found, or that the Common Ancestors found are accurate. This is just a clue.

This process uses AncestryDNA’s search function to find DNA Matches with Trees that have your specified surname/location in them. From my perspective this is a pretty powerful search technique. The results are a list of your DNA Matches (so you share some DNA with each one); and each Match has a Tree large enough to have the surname and birth place combination you specify in them. I’ve found a high percentage of these results to be my Ancestors. We must still verify both our path and the Match’s patch back to the CA. And, if we want to use the DNA segment, we must still verify that that segment is from that CA.


  1. At AncestryDNA, click on DNA (in the upper tool bar) and DNA Matches (from the drop down menu) – the result is the entire list of your DNA Matches.
  2. Click on Search (on the right side; just above your Match list) – this brings up 3 search boxes.
  3. Type a Surname in the “Surname in Matches’ trees” box; AND type a location in the “Birth location in Matches’ trees” box. Ex: CHEATHAM and Henrico County, Virginia, USA [This is one of my 7xGreat grandparents – I should get mostly 8C Matches with this search]. Use the “Include similar surnames” check box per your judgment. It’s best to use the Ancestry standards for the location, which will usually come up as a suggestion as you type.
  4. Click on the green Search button – the resulting list will be your DNA Matches who meet the criteria.
  5. Click on any Match to get their page (compared to you). You can investigate your target surname from the Shared Surnames list OR by clicking on their Linked (or Unlinked) Tree and search for that Surname.

Like all search processes, the key is finding the right combination of search terms. Clearly searching on JONES in Virginia, USA would not be helpful. My best suggestion is to search on a County, State combination.

I started with a list of my 7xGreat grandparents with their birth places. Most of these surname/birthplace combinations give me a very useful list, which often includes Matches with closer CAs (same surname and county). I can easily skip over all the ones I’ve already found and “Stared”, “Dotted”, and “Noted” – but many are new to me (ThruLines does not include any Matches beyond 6C). Also, many of the Matches with these CAs will share small DNA Segments – but they may be true genealogy cousins anyway.

If you get into a “grove” with this process, try using surnames from married daughters of your Ancestor (with the appropriate birth location). You’ll find even more Matches who had not taken their Tree back far enough…

This process ties into Triangulated Groups and/or (manual) Clustering, in that it finds more CAs to add to your Notes. You can then click on Shared Matches to see if this information would influence a Cluster or TG. By “influence” I mean that it could reinforce existing information seen in the Shared Matches, it could add evidence to extend an existing CA or Ancestral line, or it could contradict existing information resulting in a review of that TG or Cluster.

Also, if you are trying to “Dot” some of your 6-7cM Matches, this process will focus on some key Matches. When your Match list (for a surname/location) comes up, just scroll down and work up from the bottom until you’re into the 8cM Matches…

More Common Ancestors are good! They help validate the genealogy and add clues for Triangulated Groups and/or Clusters.


[AV] Segment-ology: Find AncestryDNA Matches with Common Ancestors TIDBIT by Jim Bartlett 20200808