Sewing in hair extensions means stitching wefts of hair onto braided cornrows on your scalp
A sew-in (also called a weave) is a method of attaching hair extensions by sewing them onto braided tracks that sit flat against your head. Your natural hair is braided into cornrows in the pattern where you want the extensions to sit, then the wefts—the sewn edges of the extension bundles—are stitched directly onto those braids using a needle and thread. The result is a protective style that can last four to eight weeks with proper care.
The process requires patience, the right materials, and either professional installation or significant practice if you are doing it yourself. Most people visit a stylist for this work because the braiding and stitching take skill and time—usually two to four hours depending on the amount of hair and your experience level.
Key Takeaways
- Sew-ins start with cornrow braids laid flat against your scalp, then extensions are stitched onto those braids with needle and thread.
- You will need hair bundles with wefts, a curved needle, thread that matches your hair color, scissors, and clips to hold sections in place.
- The braiding pattern determines where extensions sit, so plan which areas you want covered before you start braiding.
- Stitching requires small, tight stitches along the weft so the hair does not slip or pull loose during wear.
- Sew-ins last four to eight weeks and need regular maintenance including moisturizing your braids and avoiding excessive tension.
Materials and tools you need before starting
Gather your supplies before you begin, because stopping mid-installation to find a tool wastes time and can leave your braids incomplete. You will need hair bundles with wefts (the sewn edge at the top of each bundle), a curved needle sized for hair work (usually 18 or 20 gauge), thread in a color that matches your hair, small sharp scissors, hair clips to section off your work, and a comb or brush for detangling.
The curved needle is essential—a straight needle is much harder to maneuver through the tight space between the braid and the weft. Thread should be strong and match your hair color so stitches are less visible. Some people use waxed thread because it holds knots better, though regular polyester thread works if you tie your knots securely.
If you are installing on someone else's head, have them sit in a comfortable chair with good lighting and a mirror so they can see what you are doing. If you are doing your own hair, a handheld mirror or phone camera pointed at the back of your head helps you see the braids clearly.
Braiding the cornrow foundation
Before you sew anything, you need cornrows braided flat against your scalp in the pattern where you want extensions. The braids act as the anchor for the wefts, so they need to be tight enough to hold stitches but not so tight that they cause pain or damage to your hairline.
Start at the nape of your neck and work upward, braiding in straight lines or curved patterns depending on your desired look. Leave small gaps between braids—usually about a quarter-inch—so you have room to stitch the weft without the braids bunching together. If you are new to cornrowing, this step alone can take an hour or more. Many people have a stylist do the braiding and then sew in the extensions themselves, or vice versa.
The number of braids depends on how much coverage you want. A full head typically needs six to ten braids, though this varies based on hair thickness and the look you are going for. Thinner braids mean more of them, which takes longer but can give a more natural appearance.
Stitching the wefts onto the braids
Thread your curved needle and tie a knot at the end. Start at one end of a cornrow braid and position the weft of your first hair bundle along the top of the braid. Push the needle through the braid from underneath, then through the weft, then back through the braid—this creates a stitch that locks the weft in place.
Make small, tight stitches about a quarter-inch apart along the entire length of the weft. The tighter and closer your stitches, the more find the hair will be and the longer it will last. If stitches are loose or far apart, the weft can slip or the hair can pull away from the braid during wear or washing.
After you reach the end of the first weft, tie off your thread with a knot and trim the excess. Move to the next braid and repeat. Work methodically—rushing through stitching is the most common reason sew-ins fail early. If a stitch feels loose as you go, go back and reinforce it before moving on.
Blending and styling after installation
Once all wefts are sewn down, you can blend your natural hair with the extensions and style the full head. Some people leave their natural hair out at the roots for a more blended look, while others tuck all natural hair under the extensions for a seamless appearance.
You can curl, straighten, or braid the extensions once they are installed. If you use heat tools, use a heat protectant spray first and keep the temperature moderate—high heat can damage the hair, especially if it is synthetic. Many sew-in styles look best with loose waves or curls, which also help hide the seams where wefts are stitched.
Take a photo of the finished style so you remember how it looked when it was fresh. This helps you recreate the style after washing or if you need to explain to a stylist how you want it to look.
Caring for your sew-in between visits
A sew-in lasts longer when you moisturize your braids regularly and avoid putting tension on the installation. Spray your braids with a leave-in conditioner or braid spray two to three times a week, focusing on the scalp and the braids themselves—the extensions do not need as much moisture since they are not connected to your scalp.
Sleep on a silk or satin pillowcase or wrap your hair in a silk scarf to reduce friction and frizz. Avoid tight hairstyles that pull on the braids, as this can cause breakage and loosen the stitches. When you wash your hair, use cool or lukewarm water and a gentle shampoo, and avoid rubbing or scrubbing the braids.
If you notice a weft starting to slip or a stitch coming loose, have it reinforced as soon as possible. A small repair now prevents the entire section from coming undone later. Most sew-ins need a touch-up or tightening around week three or four.
When to remove or replace your sew-in
After four to eight weeks, your natural hair will have grown enough that the braids loosen and the sew-in becomes uncomfortable or starts to slip. At this point, it is time to remove it and either install a fresh one or give your hair a break.
To remove a sew-in, carefully cut the thread holding each weft using small scissors, then gently slide the wefts away from the braids. Do not pull hard or yank—this can break your natural hair. Once the wefts are off, unravel the cornrows slowly and detangle your hair with a wide-tooth comb and conditioner.
After removal, deep condition your hair and give it at least a week or two without extensions before installing a new sew-in. This rest period lets your scalp recover and your natural hair regain moisture. If your hair feels dry, brittle, or tender, wait longer before your next installation.
Frequently Asked Questions
Can I sew in extensions on my own hair?
Yes, though it is difficult because you cannot see the back of your head clearly and the angle makes stitching awkward. Many people braid their own cornrows but have a stylist sew in the extensions, or vice versa. If you do both yourself, use a handheld mirror or phone camera to see what you are doing, work slowly, and expect it to take longer than a professional installation.
How much does a sew-in cost at a salon?
Salon prices vary widely depending on your location, the stylist's experience, and how much hair you are installing. Costs typically range from $100 to $400 or more for the full installation, not including the cost of the hair bundles themselves. Call salons in your area to compare prices.
Will a sew-in damage my natural hair?
Sew-ins are considered a protective style and do not damage hair if installed and maintained correctly. Damage happens when braids are too tight, stitches are loose and cause pulling, or you do not moisturize your scalp and braids. Follow the care steps in this guide and remove your sew-in on schedule to keep your hair healthy.
Can I wash my hair with a sew-in in?
Yes, you can wash your hair with extensions in, but be gentle. Use cool water and a sulfate-free shampoo, and focus on your scalp and braids rather than the extensions. Avoid rubbing or scrubbing, and do not soak the hair for long periods. Pat dry gently and let it air dry or use a low heat setting.
What if a stitch comes loose during wear?
A loose stitch can cause the weft to slip or the hair to pull away from the braid. If you notice this, tie off the loose thread and reinforce that section with new stitches as soon as you can. If you are not comfortable doing this yourself, visit your stylist for a quick repair before the problem spreads to the rest of the installation.