An oversized T-shirt with drop shoulders is drafted with 16 to 25 cm (6 1/4 to 10 in) of ease at the chest, a shoulder seam that extends 5 to 8 cm (2 to 3 1/8 in) past your shoulder point onto the upper arm, and a nearly flat sleeve cap. It takes about 1.5 m (1 5/8 yd) of 140 cm (55 in) wide jersey and sews in the same five steps as any T-shirt: shoulders, neckband, sleeves in flat, side seams, hems. Use a pattern drafted oversized rather than a fitted pattern in a bigger size, because sizing up grows the neckline and the armhole out of proportion.
What do you need to sew an oversized T-shirt?
The pieces:
- Front and back, each cut once on the fold, with the extended shoulder line.
- Sleeve, cut twice, with a low cap.
- Neckband: a strip of jersey or ribbing 5 cm (2 in) wide, about 85 % of the neckline length plus 2 cm (3/4 in) for the seam, for a finished band of 1.5 cm (5/8 in).
Notions: a stretch or ballpoint needle in 75/11 or 80/12, polyester thread, 50 cm (20 in) of stay tape or clear elastic for the shoulders, and a twin needle for the hems if you have one.
Fabric: on 140 cm wide jersey, a hip-length oversized T-shirt with short sleeves takes 1.4 to 1.7 m (1 1/2 to 1 7/8 yd); long sleeves or a tunic length bring it to 1.8 to 2 m (2 to 2 1/4 yd). The extended shoulders make the front and back wide, so check that one piece fits across the folded fabric before you buy. Pre-wash the jersey and dry it the way you will wash the T-shirt.
Which jersey works best for an oversized T-shirt?
Volume needs some weight. A cotton or cotton-modal jersey of 180 to 240 gsm (5 1/2 to 7 oz) holds the boxy shape and falls in straight folds; a heavier interlock, a slub jersey or a linen jersey do the same with more texture. Very light jerseys under 150 gsm collapse against the body, show every seam through and make the shoulders look dropped by accident rather than by design.
Stretch matters less than for a fitted tee. With this much ease, 20 to 30 % stretch across the width is plenty, and good recovery keeps the neckband flat. If you are new to knits, the jersey knit for beginners post explains how to read a bolt label.
How much ease does an oversized T-shirt need?
Ease is the difference between the finished garment and your body. A T-shirt can be anywhere from slightly negative to very loose, and the shoulder follows the chest.
| Fit | Ease at the chest | Shoulder seam |
|---|---|---|
| Fitted | 0 to −5 cm (0 to −2 in) | At the shoulder point |
| Regular | 5 to 8 cm (2 to 3 1/8 in) | At the shoulder point |
| Relaxed | 10 to 14 cm (4 to 5 1/2 in) | 1 to 3 cm (3/8 to 1 1/4 in) past it |
| Oversized | 16 to 25 cm (6 1/4 to 10 in) | 5 to 8 cm (2 to 3 1/8 in) past it |
The neckline does not scale with the ease: an oversized tee still has a neck opening that sits close to your neck, which is why a size-up fitted pattern looks wrong. The armhole is lowered on purpose, by 2 to 4 cm (3/4 to 1 1/2 in), so the extended shoulder and the wide sleeve meet without pulling.
How does a drop shoulder change the sleeve?
When the shoulder seam moves down the arm, the top of the sleeve no longer has to curve over the ball of the shoulder. The cap drops from the 12 to 15 cm (4 3/4 to 6 in) of a set-in sleeve to 6 to 9 cm (2 3/8 to 3 1/2 in), and the curve flattens, so the sleeve goes in without any easing. A drop shoulder also shortens the sleeve: because the seam starts 5 to 8 cm further down the arm, the sleeve piece is cut shorter by the same amount. A short sleeve finished 15 to 18 cm (6 to 7 in) below the dropped seam ends around the elbow crease on most adults; a long sleeve is measured from the dropped seam to the wrist.
How do you sew an oversized T-shirt, step by step?
- Cut and mark. Fold the jersey selvage to selvage with the greatest stretch running around the body. If the fabric rolls or shifts, cut the front and back single layer on a traced full piece. Mark the center front and back of the neckline, the sleeve cap center and the sleeve front with a snip.
- Sew the shoulder seams right sides together with a 1 cm (3/8 in) seam allowance and stay tape in the seam. The dropped shoulder seam is longer than a normal one and carries the weight of a wide sleeve, so the tape matters more here than on a fitted tee. Press toward the back.
- Attach the neckband. Join the strip into a loop, fold it lengthwise wrong sides together and press. Mark quarters on the band and on the neckline, match them, and sew with the band on top, stretching it to fit between pins. Press the seam toward the body. How to sew a neckband on a T-shirt goes into the band length for each neckline.
- Sew the sleeves in flat. Open the body, match the cap center to the shoulder seam and the sleeve front mark to the front armhole, and sew. The cap is almost straight, so the two edges lie together without pins every few centimeters.
- Sew the side seams in one pass from the hem to the end of the sleeve, matching the underarm seams. Finish the allowances together.
- Hem the sleeves and the body with a 2.5 cm (1 in) hem pressed up and sewn with a twin needle or a narrow zigzag, letting the fabric feed without being pulled.
- Press with steam, hovering over the hems rather than ironing them flat.
What are the most common mistakes with an oversized tee?
- Sizing up a fitted pattern. The neck gapes and the armhole is deep in the wrong places. Use an oversized draft.
- Forgetting to shorten the sleeve. The drop adds length at the top; short sleeves end up at the elbow and long sleeves cover the hand.
- Neckband too long. It stands away from the neck. At 85 % of the neckline it hugs; on a wide boat neck, go to 90 %.
- A jersey that is too light. The shape collapses. Pick 180 gsm or more.
- Stretching the hem under the foot. It waves. Let the feed dogs move the fabric and lower the presser foot pressure if your machine allows it.
How do you keep oversized from looking sloppy?
Proportion does the work. A dropped shoulder with a hem at the high hip looks deliberate; the same volume at the knee looks borrowed. Keep the sleeves short enough to show the elbow or long enough to reach the wrist bone, nothing in between, and let the neckline sit close to the neck. A crisp, pressed neckband and a straight twin-needle hem are the two details that signal a made garment.
Can Sewly draft the oversized T-shirt for you?
Sewly's T-shirt pattern has an oversized fit option that moves the shoulder seam onto the upper arm and lowers the sleeve cap, with a round, scoop, V or boat neckline, sleeves from sleeveless to long, and a length from cropped to tunic. It works out the neckband length so it lies flat and uses 1 cm seam allowances on knits by default. The 3D preview, on a mannequin built from your measurements, is a quick way to judge where the shoulder lands and how long the body looks before you cut.