Ancestry Shared Matches are those that you have in common with another match. This is sometimes referred to as ICW, an abbreviation of “In Common With”. Ancestry rolled out the Shared Match tool in August 2015. There have been more recent new features, but Shared Matches remain one of the most powerful tools for your family research.
This article gives you a detailed understanding of how shared matches work, the Ancestry display threshold, and why you can’t assume shared matches have the same common ancestor. We then give nine powerful tips for using Ancestry shared matches to build your family tree.
Users of AncestryDNA can see shared matches by clicking on a particular Dna Match and looking at the Shared tab.
It’s important to know that the list on the Shared tab page is restricted to Ancestry’s chosen CM threshold. The way they put it is that they only show you “fourth-cousins-and-closer”. That translates into above 20 cM. Ancestry should try to make this a little clearer. When new members aren’t aware of the threshold, it leads to the qustion: “why aren’t shared matches working?”
AncestryDNA rolled out their Shared Match tool in August 2015. It’s interesting to read the comments from their launch post back then, that there was some immediate confusion that still crops up on message boards. Here is the misunderstanding in a nutshell:
- “Wondering why Cousin A has shared match Cousin B, but Cousin B does not show shared match Cousin A.”
- “I am confused as to how a match for me A also matches B but B does not match A.”
Here is a concrete example: as I write this, the Shared Match list of my first cousin Margaret shows five matches we have in common. I happen to know that there are another 29 Ancestry matches that list Margaret on their shared match page with me.
Take Claire, for example. If I scroll down to my “distant” cousins and open Claire F, I see that we share three matches in common. But wait! There is my close cousin Margaret at the top of Claire’s list. While Claire is nowhere to be seen on Margaret’s shared list.
This is all about the threshold that Ancestry applies when displaying shared matches i.e. the threshold of “fourth-cousins-and-closer”. Claire shares 19 cM with me, and is therefore in Ancestry’s “distant cousin” category. That stops her from showing up on Margaret’s list. But Margaret is my close cousin and above the threshold, so she shows up on Claire’s displayed list.
I think of these below-threshold shared matches as “hidden” shared matches. My cousin Margaret has 29 hidden shared matches with me. Yes, that is all the way down to the low-confidence levels of 6 and 7 centimorgans. Yet Claire at 19 cM is just outside the Ancestry threshold, and there are another two at 15 cM are above. If I choose to research matches at 10 cM and above, then there are 17 other shared matches I’d like to review.
Why this particular threshold?
I don’t really have an answer to that question, nor can I link to a definitive answer from Ancestry. It must partly be related to avoiding false shared matches. Be aware that the lower the number of centimorgans you share with a match, the higher the chance that a match is is not really your genetic relative. This is due to the inherent random nature of genetic inheritance.
However, that doesn’t quite square with the fact that Ancestry lists your matches down to 6.0 cM. Why add restrictions with one set of data and not the other? I don’t know.
My highest match on Ancestry is also named Margaret. She is my mother’s first cousin. Seven people appear on her Shared Matches tab.
Our top shared match is her daughter – that’s the easy research. Another shared match required a simple scan of his tree to discover that our common ancestor was back one generation on the same line.
But it’s important to understand that not all the shared matches in the list must descend from the same line. Maybe they will, maybe they won’t. If that doesn’t quite make sense…read the rest of this section.
Marty and Karen are at the bottom of Cousin Margaret’s Shared Matches tab. When Margaret reviews their shared matches from her own account, I turn up on both lists.
I can start with the working hypothesis that we all share the same line. But an examination of Marty’s tree leads me to believe that he is related to Cousin Margaret on his paternal line and to me on his maternal line.
And what about Karen? She has an extensive tree, but I cannot figure out the connection between us, or her connection with any other match that we share. There are gaps in my tree and gaps in Karen’s tree, and our mystery ancestor is somewhere where those gaps coincide.
But here’s the danger: Karen could have an ancestral surname in her tree that is also in mine. This could be by coincidence and bear no connection to our relationship.
So, this is what Shared Matches are NOT. They are NOT a sure-fire determination that you, your match, and your shared match are descended from the same common ancestor.
However, they ARE a great launching point for your genealogical research. The rest of this article is a series of tips on working with your shared matches to identify common ancestors.
If you’ve been able to test a parent, then Ancestry’s features will do this for you. But many are not in that position and need to use shared matches to identify a subset of paternal and maternal matches.
I think this is where many DNA testers start, and it’s a good start. You need a handful of closer cousins where you have identified their relationship to your parent.
- Open the match profile of your highest cousin.
- Use notes or a group to flag this match as maternal or paternal.
- Switch to the Shared Match tab
- Use notes or a group to flag all shared matches as maternal or paternal
- Move on to the Next Known Cousin and Repeat from Step 1
Are your Parents Related?
Here is a possible scenario: you move on to your father’s known second cousin, and flag him as a paternal match. But when you open his Shared Match tab, you see a match that already is flagged as maternal. So, your parents may be distantly related. It’s not uncommon.
Yes, this complicates your research. But look at it this way: investigating your Shared Matches has identified this complicating factor. Otherwise, you could be mystified by what DNA is telling you versus what you know from your tree.
TIP: Compare Pedigree Lines in Multiple Browser Windows
I’m sure you’ve already examined your top pages of DNA matches. You’ve reviewed their public trees to try to identify how you are related. You may have extended your own tree based on well-researched and sourced lines from your matches’ good research.
The Shared Match tab presents you with additional clues that could be the breakthrough to identify common ancestors in the triangle of you, your match, and each shared match. Read on for my most useful tips for using shared matches in your research.
When I’m researching a Shared Match list, I look for the low hanging fruit first. I focus on matches on the list who have a linked tree, and I open each pedigree page in a new tab in my browser (right-click instead of clicking). If matches are siblings, then a quick flip between browser tabs is usually enough to see that they share a deceased grandparent.
But take a look at these two match pedigree pages: the common grandparents are visually in different places. I find that I miss these unless I drag the browser tab to a new window and lay them out side by side – as I’ve done in the graphic.
At this point, I choose which tree to investigate. In the example, the tree on the left has dates, unlike the tree on the right. So, I’ll start with the tree with more details, and I go looking to see what sourced records are in the tree.
When the list of shared matches is short, you probably won’t need to use additional filtering. But think of how you approach these small lists: you scan your eye looking for the “most useful” matches to research. Sometimes a user’s display name will jump out at you e.g. you spot a surname of interest.
But more often you’re looking for “useful” trees. On a first pass through, you may skip those tiny three-person linked trees and target those juicy big trees.
With the larger lists of shared matches, don’t forget that you have the same filters on the Shared Match tab that are on the main Match List page.
My favorite filter is “Public linked trees”.
It would be nice if we could sort the filtered list by order of tree size, but we can’t with Ancestry’s interface.
Linked trees are the fastest to research. The pedigree page is a click away, and you can see where the match is situated in the tree.
When I’ve exhausted the available linked trees, I’ll move on to unlinked trees. Remember – there’s always a possibility that an unlinked tree does not represent the DNA match. You do have to be sure you’re not looking at the tree of a spouse. Check the name of the tree for clues. You can also look for an ancestral surname that is similar to the Match display name.
In my experience, matches with a single unlinked tree have simply forgotten to link it to their DNA. It’s the ones with multiple unlinked trees that I may skip altogether. I mean, one could be the spouse, and another could be the neighbor.
TIP: Be Cautious with “Common Ancestors”
Ancestry also provides a filter for “Common ancestors”. I have so few that I don’t need to use this filter. I can easily spot the little green leaf by eye.
Remember that these are suggestions from Ancestry, based on the Thrulines feature. They are based on trees, not DNA. Therefore, they are only as accurate (or inaccurate) as the trees from which they are derived. This is a link to a detailed article on how Ancestry Thrulines work.
You do need to research these independently and verify that they are correct. This link is to an article with twelve tips for using Ancestry ThruLines.
The Search feature allows you to search the Shared Matches on match name, surname, and birth location. Let’s take the surname search first. This tactic is when you’ve struck out on finding common surnames between your direct line and these shared matches.
Before we get into this, be warned that this feature does not work the way Ancestry suggests. It does not search all surnames in a tree. It only finds ancestral surnames in the direct line. If you’re not convinced, I put this to the test – check out our video on how Ancestry surname search really works.
But it can still be a useful part of your research. The strategy is to build a hit list of less common surnames in your wider branches. Look in particular for a branch with many siblings.
For example, one of my 3rd great-aunts married a “Young” and had seven sons (and six daughters). It’s not one of the more common Irish names, so it’s on my hit list of searches – particularly when I spot any shared match on the page who I suspect is somewhere within that particular branch.
A hit will show me those matches with Young in their direct line. As the name isn’t in my own direct line, it doesn’t appear in Ancestry’s “Common Ancestors” display. The Surname Search is a way of broadening out into your wider branches.
The Search feature also allows you to search on birth locations in the direct line of your matches.
My location hit list includes six villages, parishes, and small towns in Ireland that are associated with my known maternal great-great grandparents. I avoid including the more populated or larger towns. That’s easy for me to assess, as I’m Irish.
But I also have a hit list for locations within the United States, Canada, and Australia. These places took longer to compile – but a quick search on “Population of X” steers me towards what to include.
But where do you start? The “List of all People” feature in your tree is a good place. As the list is ordered by name, you’ll need to scan your eye down the pages to see clusters of place names.
Take Westfield, Union, New Jersey as an example. It pops up across various surnames in my tree, and I haven’t been able to identify the connection. I’d never heard of the place, so I asked the internet: “how big is Westfield New Jersey?” A population of 30K is small enough to go on my list.
You may have already discovered that you’re not guaranteed to get a response when you send messages to your Ancestry DNA matches. This link is to an entire article is on how to increase your chances of getting replies to your Ancestry messages.
You can utilize your shared match lists to be strategic in your approach to an interesting branch. Earlier, I showed two pedigree lines from a Shared Match tab. The DNA matches are clearly first cousins.
In one sense, having two first cousins on a shared match list is no better than just one. I mean, if their trees are identical – you may not get any extra info (although their own shared match tabs may be slightly differently).
But it gives you two chances of getting a reply! In the example, one tree had more details and sources than the other. I’d message that match first. If there’s no reply, why not try the other one? She might give her cousin a nudge!
TIP: Multiple Ancestors – Watch Out for Convergence
There are some indicators that should flag to you that there is a higher possibility than usual of multiple ancestors within a shared match list.
My parents hail from different continents, so I’m confident that there will be no shared match that connects to both my paternal and maternal side.
But my maternal line is a different story. My eight maternal great grandparents are from the same county in Ireland. Two are from adjoining parishes. This is one indicator that I must watch out for inter-marriage across the branches in my tree. You may not have such a localized tree, so what should you watch out for?
Convergence in Place and Time
No, we’re not talking astrophysics here.
Keep notes on any two branches in your tree where there are birth or death locations within the same region and within a similar time frame. This should nudge you towards looking for marriage across the branches.
The best way to spot convergence is to keep entering the lowest jurisdiction that you can identify for birth and death locations. This is a general genealogical guideline, but it really helps to make sense of shared matches. This link is to an article on guidelines for entering locations in your tree.
I try to enter parish names for U.K. and Irish locations, and town or county for U.S. locations. “Ireland” or “New York” isn’t helpful here.
Ancestry doesn’t make it easy to spot these common locations in your tree. You can’t sort the “List of All People” by place name. That’s why I suggest keeping separate notes. You could use a spreadsheet for this purpose. Alternatively, you can supplement your Ancestry research with third-party software that does a better job with tracking locations.
TIP: Using Software to Identify Common Locations in your Tree
Several third-party family tree applications will show you common locations. For example, the free MyHeritage Family Tree Builder lets you view a breakdown of your place names.
In the example here, I’ve sorted by the number of times that a place name appears in my tree. I was surprised when I first used the software that the New Jersey district is so prevalent. It appears more often than the hometown of my grandfather. I couldn’t remember any one research stint adding a boat load of New Jersey entries, so I hadn’t made any particular note about this location.
Family Tree Builder helps shed some light on this. The software will list all persons in your tree that refer to a selected location.
You don’t need to have a tree on MyHeritage to use the features I’ve mentioned. You can export your tree from Ancestry as a GEDCOM file and import it into the free software. Additional features, such as visual mapping, require creating a MyHeritage account and possibly a subscription.
Aside from Family Tree Builder, there are other commercial applications that will do similar.
I’ve reviewed the free RootsMagic Essentials application for downloading your tree and media from Ancestry. The free version gives you a simple list of place names. If you upgrade to the paid version, you can run reports on people per location.
I’d be surprised if Family Tree Maker didn’t offer similar functionality.
We’re planning more articles on advanced tips and techniques for using Ancestry shared matches.
Looking for an e-book on building your Ancestry tree?
Check out our e-book on building your family tree with Ancestry.com. It’s available on Amazon now!
Packed with practical strategies and techniques for using Ancestry features to build out your tree.
- Setting up your DNA-linked tree
- Using your tree to find connections with DNA matches
- Best practices for entering names, dates, and locations
- Strategies for getting the most benefit from Hints
- Tips for using powerful Search features
- Sending messages that get replies
How about some Video Tutorials?
If you would like to watch some short video tutorials that walk through using Ancestry features step-by-step, browse through the DataMiningDNA YouTube channel.