How to Sew a Tote Bag With Boxed Corners

A lined tote bag with boxed corners takes about 90 minutes and needs only straight seams. Cut a 2 inch (5 cm) square from each bottom corner and sew the gap shut to give the bag a flat, 4 inch (10 cm) deep base.

What do I need to sew a tote bag?

The numbers below make a bag about 15 inches (38 cm) wide and 13 inches (33 cm) tall. For a precise plan with sizes, see the free Boxed Tote Bag, which comes in Regular and Large.

Outer fabric: two pieces, 16 x 16 inches (40 x 40 cm). Canvas, denim or heavy quilting cotton works well.
Lining fabric: two pieces, 16 x 16 inches (40 x 40 cm). Quilting cotton is fine.
Straps: two strips of 4 x 22 inches (10 x 56 cm).
Tools: a sewing machine, thread, scissors or a rotary cutter, pins, an iron, a ruler and a fabric marker.
Needle: size 90/14 for canvas, 80/12 for cotton. See the needle guide.

Use a ½ inch (1.3 cm) seam allowance throughout.

How do I make the straps?

Fold each strap strip in half lengthwise and press a center crease.
Open it up, fold both long edges in to meet the crease and press.
Fold in half again so the raw edges are hidden. The strap is now 1 inch (2.5 cm) wide.
Topstitch along both long edges, ⅛ inch (3 mm) from the edge.

How do I sew the outer bag?

Pin the two outer pieces right sides together.
Sew down one side, across the bottom and up the other side. Leave the top open.
Press the seams open.
Pin the straps to the top edge, 4 inches (10 cm) in from each side seam, with the raw ends even with the raw top edge. Baste them in place with a scant ¼ inch seam. Make sure the straps are not twisted.

How do I box the corners?

This is the step that gives a tote its shape. It looks tricky but is straightforward.

With the bag still inside out, flatten one bottom corner so the side seam sits over the bottom seam and forms a point.
Measure 2 inches (5 cm) from the point along the seam and draw a line across.
Sew along that line, then sew it a second time for strength.
Trim off the point ½ inch (1.3 cm) beyond the stitching.
Repeat on the other corner.

A 2 inch (5 cm) box gives a base about 4 inches (10 cm) deep, so the bag stands up and holds more. Use 1½ inches for a slimmer base or 3 inches for a roomy one.

How do I make the lining?

Pin the two lining pieces right sides together. Sew the sides and bottom, but leave a 5 inch (13 cm) gap in the bottom seam for turning.
Box the corners the same way as before.
Press the seams open.

How do I join the lining and the outer bag?

Keep the outer bag inside out and the lining right side out. Slide the outer bag into the lining, so the right sides face each other and the straps are sandwiched between them.
Match the side seams and pin around the top edge.
Sew all the way around the top with a ½ inch seam.
Pull the whole bag out through the gap in the lining.
Close the gap with a ladder stitch or by machine, ⅛ inch from the edge.
Push the lining into the bag, press the top edge and topstitch ¼ inch (6 mm) from the top. This also holds the straps in place.

Mistakes to avoid

Twisting the straps. Check before you sew the top seam.
Forgetting the gap in the lining, which leaves you stuck with a closed bag.
Skipping the second row of stitches on the strap ends. Straps carry the most weight.

Make it with Sewzy

Sewzy's Boxed Tote Bag is a free beginner pattern of about 90 minutes in Regular and Large. It comes with a print-at-home PDF (Letter, A4 and an A0 copy-shop file) and a written step-by-step guide. A matching Zipper Pouch makes a nice set. The AI sewing coach is there for any step that is unclear. Sewzy is iPhone only: $3.99 per week or $29.99 per year, with a 3-day free trial. Get Sewzy on the App Store. More bags are on the bag sewing patterns page.

FAQ

How do I box the corners of a tote bag?

Flatten each bottom corner so the side seam lies over the bottom seam, mark a line across the point and sew it. A 2 inch box gives a base about 4 inches deep.