AncestryDNA Match Categories List: Exploring Your Relations

Q: What does "Half-Cousin" mean?

A half-cousin is the child of your parent's half-sibling . They share about half the DNA of a normal cousin (approx. 400 cM instead of 800 cM).

When you open your AncestryDNA results, the first thing you see is a list of strangers labeled “1st Cousin,” “2nd Cousin,” or “Close Family.”

It is important to understand that these labels are estimates, not facts.

Ancestry’s computer doesn’t know exactly who these people are. It only knows how much DNA (measured in centimorgans) you share. It then assigns a label based on probability. This guide explains exactly what each category means, the genetic ranges for each, and how to tell if a “1st Cousin” is actually a Great-Aunt.

Table of Contents

Why AncestryDNA Match Labels Are Only Estimates

Before diving into the categories, you need to understand two key terms that appear frequently in your match list.

1. What does “Removed” mean?

“Removed” simply means different generations.

Once Removed: You are one generation apart (e.g., your parent’s first cousin, or your first cousin’s child).
Twice Removed: You are two generations apart (e.g., your grandparent’s first cousin).

2. Centimorgans (cM)

This is the unit of measurement for shared DNA. The higher the number, the closer the relationship. You can learn the specific math behind this in our guide on how to figure out relationships via AncestryDNA.

AncestryDNA Match Categories Explained (Closest to Distant)

Ancestry groups your matches into “buckets” based on shared cM levels. Here is the breakdown from closest to most distant.

1. Self / Identical Twin

Shared DNA: ~3,400+ cM (100%)
Who falls here: Only you or an identical twin.
Note: If you see a stranger in this category, it is a definitive sign of an identical twin separated at birth.

2. Parent / Child

Shared DNA: ~3,300 – 3,700 cM
Who falls here: Biological Mother, Biological Father, Son, or Daughter.
Accuracy: 100%. DNA cannot mistake a parent for a sibling.

3. Full Sibling

Shared DNA: ~2,200 – 3,300 cM
Who falls here: Full Brother or Full Sister (sharing both parents).
Note: If you share around 1,700 cM, the person is likely a Half-Sibling, not a Full Sibling.

4. Close Family

This is the most confusing category because it covers several different relationships. Ancestry uses this label when the DNA is too high for a cousin but too low for a parent.

Shared DNA: ~1,300 – 2,200 cM
Possible Relationships:
- Grandparent / Grandchild
- Aunt / Uncle
- Niece / Nephew
- Half-Sibling (sharing only one parent)
How to tell them apart: You must look at their age. If the “Close Family” match is 25 years older than you, they are likely an Aunt/Uncle. If they are your age, they are likely a Half-Sibling.

5. 1st Cousin

Shared DNA: ~550 – 1,200 cM
Possible Relationships:
- Biological 1st Cousin (child of your Aunt/Uncle)
- Great-Grandparent
- Great-Aunt / Great-Uncle
- Half-Aunt / Half-Uncle
Nuance: A really close 1st cousin can sometimes look like an Aunt (lower end of Close Family).

6. 2nd Cousin (and 1st-2nd Cousin Range)

Shared DNA: ~200 – 600 cM
Possible Relationships:
- True 2nd Cousins (you share Great-Grandparents)
- 1st Cousins Once Removed
- Half-1st Cousins
Strategy: At this level, you usually need to use Ancestry ThruLines to visualize how you connect, as the paper trail gets harder to follow.

7. 3rd Cousin and 4th Cousin

Shared DNA: ~20 – 200 cM
Possible Relationships: 3rd Cousins, 4th Cousins, or various “Removed” cousins.
Reliability: Matches in this range are real, but identifying the exact ancestor is difficult without a well-built family tree.

8. Distant Cousins (5th – 8th Cousin)

Shared DNA: 6 – 20 cM
The Danger Zone: Matches under 10 cM have a high chance of being “False Positives” (identical by chance, not by descent).
Advice: Don’t spend too much time researching a 6 cM match unless they have a very specific surname you recognize.

Frequently Asked Questions

Why is my Aunt listed as “Close Family” instead of Aunt?

Ancestry does not use specific labels like “Aunt” or “Grandma” because genetically, those relationships look identical. An Aunt shares ~25% of your DNA, and a Grandmother also shares ~25%. Ancestry plays it safe by grouping them both into the generic “Close Family” bucket.

Can a “Full Sibling” match be wrong?

No. The amount of DNA shared between full siblings is massive and distinct. If someone shows up as a “Close Family” or “1st Cousin” match, they are definitely not your full sibling—they are likely a half-sibling or first cousin.

Why do I have matches that my full sibling doesn’t have?

This is normal! You inherit 50% of your parents’ DNA, but it is a random 50%. Your sibling inherited a different random mix. You might have picked up a small segment of DNA from a distant ancestor that your sibling didn’t get. This is why it is valuable to link your DNA test to a tree and test siblings if possible—to capture all the matches.

What does “Half-Cousin” mean?

A half-cousin is the child of your parent’s half-sibling. They share about half the DNA of a normal cousin (approx. 400 cM instead of 800 cM).

Is a 6 cM match worth researching?

Usually, no. Unless you are an advanced genealogist doing “Chromosome Mapping,” a 6 cM match is too distant to confirm reliably. Focus on matches of 20 cM or higher.

Conclusion

The labels on Ancestry are just the starting point. By comparing the centimorgan counts against the ages of your matches, you can look past the generic “1st Cousin” label and figure out exactly where these people fit into your family puzzle.