Demystifying the Single Welt Pocket: A Sewing Tutorial

The single welt pocket is a staple of business attire, commonly found on blazers, pants, and the occasional dress or skirt. Differing from a patch pocket, the single welt pocket is a pocket inside your garment, with a strip of fabric covering the pocket opening on the outside of the garment.

While there are many ways to go about welt pockets, this tutorial covers the basic insertion of a single welt pocket with step-by-step instructions that are clarified with pictures. Once mastered, this easy technique, though somewhat time-consuming (it will take about an hour), will add a touch of elegance to your garments.

Materials Needed
Fabrics: Garment fabric, pocket bag fabric (can be the same or different from your garment fabric)
Thread, fabric marking instrument of choice (please pick chalk or fabric pens), fusible interfacing (with a preference for woven/weft), ruler, scissors, pins, sewing machine.

Anatomy of the Single Welt Pocket

The single welt pocket consists of a few pattern pieces which are all cut on grain out of washed, dried, and ironed fabric:

Pocket bag (so cut 2)
Welt (cut 1 in same or contrasting fabric)
Interfacing (cut 1)

Measuring your pocket

You are going to fit you pocket to the size of your garment. In my case, I cut out the pattern piece for my dress and based the pocket measurement off what looked proportionate while still being able to hold my phone–pockets need to be functional after all. One key point, the width of the pocket is the same as the width of the welt. So figure out how wide you want your welt to be and work from there.

Once you figure out your measurement, in my case 5.75″, then we need to figure out the height of the welt. I went for a tall welt as the pockets are on a dress that can support the larger detail. My welts are 1.5″ tall. Now to discern the finished pattern piece size: we’re going to add a 3/8″ seam allowance to all sides of the welt. This means that the final pattern piece for the welt is 6.5″ x 3.75″. How we get the height is the welt is folded over on itself, so there is no seam at the top of the welt (see pictures below as to how to sew the welt).

The pocket bag should also be 6.5″ wide and as deep as you feel appropriate.

Cut your interfacing a minimum of 2″ wide (I used 3″) and 1″ longer than your welt pattern at least (mine is 7.5″)

Tutorial

First, decide where on your garment you want your pocket to be. Choose carefully, once in place, the pocket cannot be moved and the fabric cannot be mended. You can set the pocket straight or at an angle (mine is at a slight angle).

Mark the fabric with the width of your pocket exactly where you want it to be with your marking instrument. I used 2 dots with a red pen so you can see it on pictures–don’t be like me, use chalk.

2. Time to interface! Apply interfacing to the WRONG side of your garment fabric centered directly over the marked pocket opening. Draw your pocket opening line on your interfacing so it is easy to see. Flip garment over and mark line on RIGHT side of fabric as well with disappearing ink or chalk.

3. Now we sew! Take your welt piece, fold it in half hotdog (lengthwise) with right sides together so the two short ends are even. Sew the short ends with a 3/8″ seam. Cut the corners to remove bulk.

4. Turn welt right side out, take a blunt tipped object to gently push out corners, and press.

5. On the RIGHT side of your garment, place your turned and pressed welt piece along your pocket placement line, ensuring the raw edge is on the line, not the folded edge. Pin the welt in place.

6. Grab one of your pocket bag pieces and place it directly overtop your pinned welt piece. There should be an overhang of 3/8″ on either side of the welt–this is your pocket bag seam allowance and it should be there. Pin the pocket bag piece in place. Sew all three layers 3/8″ from the pocket placement line, sewing through where the welt is ONLY, do not sew the pocket bag seam allowance down.

7. Grab the other pocket bag piece and pin it so it is directly butting up against the sewn welt and pocket bag pieces. The two should be touching on the pocket placement line. Sew the second pocket bag piece 3/8″ from the pocket placement line, starting 3/8″ in from the edge to ensure you do NOT sew down the pocket bag seam allowance.

8. Turn your work to the WRONG side and slash the pocket placement line, creating triangles at the ends by stopping 3/8″ before the end of the pocket line, cutting diagonally to the end of the stitch lines on either side of the end of the pocket placement line. This should look like a “Y” shape once you have finished cutting. Do not cut through the stitch lines.

9. Pull the pocket bag pieces through the now slashed opening to the WRONG side of the garment. Smooth out bubbles and crinkles until flat and press. The welt should remain on the RIGHT side of the garment.

10. Pin the pocket bag pieces together by aligning the raw edges, one will be longer than the other; this is to be expected as they are placed at different heights. NOTE: the little triangle from the “Y” shape should be folded back and pinned to the raw edge of the pocket bag piece.

11. Sew the pocket bag pieces together, including catching the triangle piece. Your seam allowance is 3/8″.