What Is a First Cousin Once Removed? (With Relationship Chart)

"Once removed" is one of those genealogy phrases that sounds more complicated than it is. People hear it and assume it means something distant or vague, when really it's describing something very specific: a difference in generation between two relatives. Once you understand that one idea, first cousin once removed - and every other "removed" relationship - stops being confusing.

The Two Rules That Explain Everything

Every cousin relationship comes down to two separate questions:

1. How many "greats" back do you have to go to find the shared ancestor? This determines whether you're first cousins, second cousins, third cousins, and so on.
2. Are you and your cousin in the same generation, or one generation apart? This determines whether the relationship is "once removed," "twice removed," or not removed at all.

A first cousin shares a grandparent with you and is in your own generation. A first cousin once removed also connects to you through that same shared grandparent-level ancestor, but is one generation up or down from you - either your parent's first cousin, or your first cousin's child.

First Cousin Once Removed, Visually

Shared Great-Grandparent
└── Grandparent A                    └── Grandparent B
    └── Your Parent                     └── Your Parent's First Cousin
        └── You                             └── Their Child
                                                  = Your First Cousin Once Removed

In other words: your parent's first cousin is your first cousin once removed. And going the other direction, your first cousin's child is also your first cousin once removed. The relationship works both ways across the generation gap.

The Cousin Chart

Relationship to you	Shared ancestor	Generation gap
First cousin	Grandparent	Same generation
First cousin once removed	Grandparent (of one of you)	One generation apart
First cousin twice removed	Grandparent (of one of you)	Two generations apart
Second cousin	Great-grandparent	Same generation
Second cousin once removed	Great-grandparent (of one of you)	One generation apart

Two Common Ways You End Up With a First Cousin Once Removed

Going up a generation: Your parent's first cousin is your first cousin once removed. This is probably the more common way people encounter the term - it's what you'd call the person your dad or mom grew up calling "cousin," one generation removed from you.

Going down a generation: Your first cousin's child is also your first cousin once removed. From that child's perspective, you're their first cousin once removed too - the relationship label is identical looking from either direction, just applied to different people.

Why This Term Trips People Up

Most of the confusion comes from everyday speech, where people often just say "cousin" for any relative of roughly their own extended generation, regardless of the exact generational math. That's perfectly fine in casual conversation, but it becomes a problem when you're documenting a family tree, writing a family history, or trying to figure out who's actually eligible for something like a family inheritance or a DNA-match interpretation - contexts where the precise relationship matters.

DNA testing services in particular have made "once removed" relationships much more visible to ordinary people, since a shared-DNA match report will often list an unfamiliar name as your "1st cousin 1x removed" with a percentage of shared DNA attached, and it's genuinely useful to know what that means before you start reaching out to a stranger claiming a family connection.

Quick Ways to Check Your Own Family

A few practical steps if you're trying to place someone in your own tree:

• Find the shared ancestor first. Trace both your line and the other person's line backward until they meet at a common ancestor.
• Count the generations on each side separately. If it takes you three steps back to reach the shared ancestor, and it takes them two steps back, the "cousin" number is based on the shorter of the two counts, and the difference in steps is the "removed" number.
• The number of "removed" always equals the difference in generation count, not the number of steps on either side individually.

Frequently Asked Questions

Is a first cousin once removed the same as a second cousin?

No, and this is the most common mix-up. A second cousin shares a great-grandparent with you and is in your own generation. A first cousin once removed shares a grandparent-level ancestor but is one generation apart - a completely different relationship despite sounding similar.

Is my first cousin once removed considered a close relative?

It depends on context, but genetically and socially, a first cousin once removed is generally considered closer than a second cousin, since the shared ancestor (a grandparent, rather than a great-grandparent) is nearer in the family tree.

Can a first cousin once removed be older or younger than me?

Yes, either is possible. If it's your parent's cousin, they're typically older. If it's your first cousin's child, they're typically younger. The generational relationship stays the same either way.

How much DNA do first cousins once removed typically share?

On average, around 6.25%, roughly half of what first cousins typically share (about 12.5%), since the extra generation dilutes the shared DNA by half.

What do I call my first cousin once removed's children?

Your first cousin once removed's children would be your first cousins twice removed, continuing the same pattern one generation further.