How you join your crochet pieces is the difference between "homemade" and "handmade." Two seams cover almost everything: the nearly-invisible mattress stitch, and the quick, sturdy whipstitch. Here's when and how to use each.
What you need
A blunt yarn or tapestry needle, the same yarn you used for the project (or a matching colour), and your two pieces laid out the way they'll be joined. Pin them first if it helps.
Mattress stitch — the invisible seam
The mattress stitch joins two pieces edge to edge so the seam virtually disappears on the right side. It's the go-to for sweaters, bags and anything where a smooth finish matters.
- Lay both pieces side by side, right sides up, edges touching.
- Thread your needle and secure the yarn at the bottom of one edge.
- Insert the needle under the corresponding bar or stitch on the opposite piece, then back on the first — working like lacing a shoe.
- Alternate side to side, gently pulling the yarn so the seam closes and lies flat.
- Weave in the ends securely when finished.
Whipstitch — fast and sturdy
The whipstitch wraps the yarn over both edges, creating a quick, strong join with a small visible ridge. It's perfect for joining amigurumi limbs, granny squares, and anywhere speed matters more than invisibility.
- Hold the two pieces together, edges aligned (right sides together for a hidden ridge, or wrong sides together for a decorative ridge).
- Insert the needle through the matching stitches of both pieces.
- Bring the yarn over the top edge and insert through the next pair of stitches.
- Repeat along the seam, keeping even tension.
- Fasten off and weave in the ends.
Mattress vs whipstitch: which to choose
| Mattress stitch | Whipstitch | |
|---|---|---|
| Look | Nearly invisible, flat | Small visible ridge |
| Speed | Slower, more precise | Fast |
| Best for | Garments, bags, motifs | Amigurumi parts, granny squares |
| Strength | Strong & neat | Very sturdy |
A few seaming tips
Use the same yarn weight as your project for an even seam, leave a long tail when you fasten off pieces so you have enough to sew with, and match your stitches one-to-one so the seam doesn't pucker or stretch. For attaching amigurumi limbs neatly, see our guide on sewing amigurumi parts.
Practise on a multi-piece make
Granny-square bags and amigurumi are perfect for practising seams. Browse our bags & accessories and amigurumi patterns.
Browse all patterns →Frequently asked questions
What is the best way to seam crochet?
For a nearly invisible, flat join use the mattress stitch; for a fast, sturdy join use the whipstitch. Choose based on whether you want the seam hidden or speed matters more.
What is the difference between mattress stitch and whipstitch?
The mattress stitch is nearly invisible and lies flat, ideal for garments; the whipstitch is faster and leaves a small visible ridge, ideal for amigurumi and granny squares.
How do I join granny squares?
The whipstitch is a quick, sturdy way to join granny squares. For a flatter, more invisible join, use the mattress stitch or a join-as-you-go method.
What needle do I use to seam crochet?
A blunt yarn or tapestry needle, threaded with the same yarn you used for the project or a matching colour.
Neat seams plus blocking are the two finishing skills that make handmade crochet look truly professional. New to it all? Start with our complete beginner's guide.
