In part one of this series, I went over the basics of understanding your AncestryDNA test—what your ethnicity estimate can tell you, what centimorgans mean, and how to understand the different relationships Ancestry presents to you. If you aren’t sure about these basics, I definitely suggest you check out my first post How to Understand Your AncestryDNA Test Results (Even If You’re Confused by Cousin Matches) — Part One.

Now it’s time to take the next step: sorting DNA cousin matches and using other people’s family trees to start to identify how you’re connected. I’ll walk you through how to make sense of it all, but don’t worry—I’m here to help if you get a little stuck.

Why Sorting DNA Matches Matters

Sorting your DNA matches turns a confusing list into useful, actionable information that furthers your genealogy research. It’s the best way to make sense of your results and start identifying where each match fits in your family tree.

The Benefits of Sorting Matches

Easily identify which branch of the family a cousin match comes from
Find recurring last names and locations in your matches’ trees to identify unknown ancestors
Stay organized from the start, making it easier to revisit specific matches and cousin clusters later in your research

How to Start Sorting Your Matches

The most common (and beginner-friendly) way to start grouping your DNA matches is by figuring out which grandparent’s branch of the family they belong to. By using what you already know about your relatives, plus the information in match trees and genealogical records, you can begin building out four basic groups.

Sorting by Grandparents with Ancestry’s Group Tools

AncestryDNA shows how closely you and a match are related in centimorgans (cM). The default match list displays your closest relatives first, based on the amount of shared cM. These are the easiest matches to start sorting.

You can create colour-coded groups and add notes to individual matches, which makes organization so much easier. Start by creating group labels for each of your four grandparents’ family lines. I like using labels like “Jones – paternal grandmother” and “Smith – maternal grandfather,” but you can use whatever naming system works for you. By creating four groups, you have four main lines that your cousin matches can be grouped into. If you don’t know your grandparents’ names, you can create placeholder labels like “Paternal 1” and “Paternal 2” and update them later.

Using Known Relatives to Build Groups Quickly

Identify matches you already know the relationship to. For example, my paternal grandmother tested her DNA, so I can confidently label any matches she shares DNA with as coming from her side of the family. My father’s first cousin on his father’s side also tested, so I can label matches connected to her as part of my paternal grandfather’s line. Just from those two relatives, I can confidently sort dozens of matches and know which side of the family they come from.

If you’re an Ancestry subscriber or on a free trial, Ancestry’s SideView feature can show which side of the family a match is likely from, based on their analysis. This is especially helpful if you don’t have many known relatives in your match list. In these cases, centimorgan amounts and clues from user trees become even more important for sorting.

Using Shared cM to Prioritize Matches

Here are some general guidelines when working with cM amounts:

Over 200 cM: These matches are usually first to second cousins. Focus on them first to identify which side of the family they belong to and who your shared matches might be
20–200 cM: These range from second to fourth cousins, often connecting you to your great-grandparents or second/third-great-grandparents
Under 20 cM: These can sometimes be false matches caused by small segments inherited from distant shared ancestors. Always verify these with solid genealogical evidence before assuming a relationship.

Using and Comparing User Trees to Create Cousin Clusters

Big disclaimer here: never assume someone else’s tree is 100% correct—fact check everything! But user trees can be incredibly helpful for grouping matches and building cousin clusters that descend from the same ancestors.

What to Look For in User Trees

On Ancestry, you can view public trees connected to DNA tests, which show all deceased ancestors in the match’s tree. Here’s what to look for:

Shared surnames: Names that appear in both your tree and theirs
Locations: Places where your ancestors and theirs lived
Time periods: Ancestors living in the same place and time as yours

Red Flags to Watch For

Copied or incorrect trees: Always double-check facts before adding anyone to your own tree
Private or no trees: It’s okay to reach out politely to see if they’re willing to share
Small trees: A tree with only a few names may not be helpful—look for 3+ generations

Compare Their Tree to Yours

Once you see potential overlaps, compare their tree to yours to look for common ancestors. This is where having your own tree built out to at least your great-grandparents can really help clarify connections.

Common Beginner Pitfalls (and How to Avoid Them)

We all get caught up in the excitement of new DNA results and make a few mistakes. I’m guilty of it myself! Here are the most common ones I see:

Focusing only on high matches: Distant matches can be the key to breaking down a brick wall.
Assuming surnames equal a match: Always verify with sources. Some surnames are very common.
Not using notes or groups: Even quick notes can save you time later
Getting discouraged: Genealogy is a marathon, not a sprint. Progress can take time, and that’s okay!

Feeling Stuck? You’re Not Alone

Sorting DNA matches can feel overwhelming, especially when you’re just getting started. Many people feel confused by cousin matches and unsure where to start—but you don’t have to figure it out alone.

I offer friendly, expert DNA services to help you move forward with confidence:

DNA Match Clarity Session ($99 CAD)

Get clear explanations of your top matches, with a visual map of relationships. Perfect for beginners.
Find out more.

DNA Lineage Discovery ($299 CAD)

Focused research into one family line, including tree building and a written timeline.
Find out more.

Want to Find Out How I Use Genetic Genealogy to Solve Family Mysteries?

Check out my blog post Finding My Grandma’s Long-Lost Uncle: How I Solved My First DNA Mystery Using Genetic Genealogy

How to Understand Your AncestryDNA Matches – Part Two: Sorting, Relationships, and Tree Comparisons