The Simple Way to Sew a T-Shirt Neckline

Whether you are new to sewing or not, getting creative with your sewing projects is one of the awesome things about sewing. YOU get to decide the colour of the fabrics you use. YOU get to decide what embellishments you can make. And sometimes, YOU get to decide which technique you want to use for a particular step.

For instance, T-shirt necklines. There are a number of fabric options you could choose, a variety of different stitches you could use, and even a number of ways to sew the neckline together.

I am going to make it really easy for you and show you the simplest, cheapest way to sew a T-shirt neckline using supplies you almost surely already have in your fabric stash.

This sewing tutorial will walk you step-by-step through the whole “How do I sew a professional looking T-shirt neckline?” process- accompanied by loads of photos!

Let’s do this!

Disclosure: This post may contain affiliate links, meaning that I get a small commission if you decide to make a purchase through my links, at no extra cost to you.

What Type of Fabric Should I Use to Sew a T-shirt Neckline?

Just like your T-shirt, you’ll want to use a soft and stretchy fabric. The 2 most popular fabrics to use are either jersey (aka knit) or ribbing.

I’m going to show you how to finish off a T-shirt neckline using jersey.

Why sew a neckline with jersey?

Jersey can look just as lovely and professional on a neckline as ribbing. But it does have a couple of advantages over ribbing.

After sewing a T-shirt together, you surely have some leftover fabric pieces, right? And you’ve quite probably got some other scraps of jersey at home from previous sewing projects. Sewing a neckline on a T-shirt is the perfect way to use some of those leftovers. And as you’ll see in a moment, you don’t need much fabric at all. No panicky shopping for a small band of ribbed stretch fabric.

Another advantage of using jersey, is that it comes in practically an infinite variety of colours and patterns. That means you can be assured of creating a T-shirt and neckline with perfectly pleasing, complimentary colours, using the same fabric as the rest of the T-shirt, or something else wilder and entirely unique. (The wilder the better, if you ask my kids 😉).

Tutorial: How to Sew a T-Shirt Neckline

Step 1

Ok, first up, you need to choose your fabrics and sew all pieces of your T-shirt together EXCEPT for the neckline.

Step 2

Next, you need to figure how much jersey you are going to need for the neckline piece you wish to sew in place.

The HEIGHT of the piece of jersey you will need is 4cm. This is ideal for any T-shirt neckline, regardless of whether you are sewing for children, women or men.

Now for the LENGTH… This is the part that will be different for each project, depending on your pattern and what size person you are sewing for.

Using a measuring band, without stretching your fabric, measure the length around the inside of the open neckline rim.

A good rule of thumb for jersey is to cut a piece 80% of the length of the neckline. This means you need to figure out what 80% of the length you just measured equals. And then before cutting, add on a seam allowance!

For example, if the neckline you just measured was 51 cm, you’ll need to cut a length of jersey 51 cm x 80% = 40.8 cm then add on a 2 x 1 cm seam allowance. That means 40.8 cm + 2 cm = 42.8 cm. Let’s just call it 43 cm, OK? So now you know you need to cut a strip of jersey 43 cm long x 4 cm high.

Step 3

Once you’ve cut a strip of jersey the correct length for your T-shirt, fold the strip in half so that the short ends overlap and the right sides are together. Pin in place.

Sew along the short edge using a 1 cm seam allowance.

If you wish, trim off some of the excess seam allowance along that short edge.

You now have a ring of jersey fabric 4 cm high.

Flip the loop so that the right sides are now facing outwards.

Fold the loop in half along its length so that the wrong sides are now together and out of sight.

Step 4

In this step you will use pins to create quarter segments along the length of the jersey piece. Pin the 2 layers together at the seam you just sewed. Picture the numbers around a clock. Let’s call this the 12 o’clock position.

Fold the loop in half and lay it flat so that this one pin is at one end of the loop. At the opposite end of the loop, pin the layers together. These 2 pins should now be across from each other. This second pin in now in the 6 o’clock position.

Lay the loop flat again so that they 1 pin is lying directly on top of the other.

Again, pin together the layers at each end of the loop. These 2 pins form the 3 o’clock and 9 o’clock positions.

Have a look at the loop of jersey. The 4 pins should be evenly spaced around the length of fabric. Just like cutting a clock into quarters!

Step 5

Now you need to mark out corresponding quarter segments along the T-shirt neck opening.

Fold the T-shirt in half lengthways, and mark both the front centre and back centre of the opening with pins.

Hold one pin in each hand and pull the neck opening outwards so that the 2 sleeves are now laying against each other and the 2 pins are opposite each other.

Now fold the neck line in half so that the 2 centre pins are atop each other and the sleeves are approximately- but not exactly! – folded in half.

You’ll notice that the fold is approximately 1 cm forward of the shoulder seam. (This is because the neck opening rises up higher at the back of all T-shirts.)

Pin at the fold and repeat with the other side of the neck opening. Now you have created 4 equal quarters around the neck opening.

Step 6

Time to pin the jersey loop into the neck opening.

Align the seam of the jersey loop with the pin and the centre back of the T-shirt. Pin in place.

One by one align the remaining 3 pins marking the loop with the remaining 3 pins around the neck opening. Using equally-spaced pins, the loop is now attached to the neck opening.

Optional Helper Step

You could sew the neckline in place already with just those 4 pins in place, stretching as you go. I prefer to add a few more pins to ensure the jersey neckline is firmly in place and doesn’t slip while being sewn.

Hold 2 neighbouring pins and stretch the jersey loop and place another pin in the centre.

Repeat around the length of the jersey loop.

Step 7

Using a 1cm seam allowance on your sewing machine, sew the fabrics together around the entire length of the T-shirt neck opening and the jersey loop

Huzzah! Your T-shirt now has a neckline!

Technically, there is no reason why this T-shirt cannot be worn now. Yay! Great job!

However… there are a couple of small tricks you can do to make your creation look more professional. Psst! I’m talking about more than just cutting off the loose threads!