It’s a little unfair that small bust adjustments don’t get talked about as often as Full Bust Adjustments (FBA) – they’re just as easy and just as not scary. hehehe
Much like the FBA tutorial we covered last time – small bust adjustments (SBA) are nothing to be afraid of. Before we start let’s ask some of the same questions:
WHAT THE HECK IS IT??
Most patterns are drafted on a B cup – so if you are smaller than a B cup you may end up having trouble fitting patterns. You’ll probably need to alter your pattern to get the right fit over your bust – when we’re talking about reducing the bust of a pattern that’s called a small bust adjustment.

DO I NEED TO DO ONE??
How do you know if you need to do an SBA on your pattern?
Easy! You know that nifty size chart you get on the back of your pattern envelope? If you find that your bust measurement falls in a smaller size column than the rest of your body – then you’ll probably need to do one. If you’ve already made a muslin, you might notice you need to do an SBA because things just aren’t quite right in that area. Some symptoms may include:
- excess fabric and sagging around the bust area (oh dear!);
- the bodice of your dress being too large around your bust, even though it fits perfectly over the rest of your body;
- the dart apex hitting you too low.
Ok cool. So now we know if we need one. Shall we begin the alteration?
CALCULATE THE SIZE OF YOUR SBA

Calculating the size of your SBA is similar to what we did this morning for FBA. It’s easy as pie. Just figure out what size you would be if you used your bust measurement – then compare it to what size you would be if you used your other measurements to determine your size. On the bodice front of the pattern, measure the distance between these sizes. This is your SBA amount! We will be reducing the bust by that much.
For example, if you fall in a size 4 for your bust measurement, but fit into the size 8 category for the rest of your measurements, then you would measure the difference between the x-small and small front pattern pieces. Whatever the difference is, you would use that number as your SBA and use the small pattern piece to create it.
DRAW YOUR SLASH LINES
Now the fun part. Let’s draw some crazy lines all over our patterns. Kidding. They’re not crazy, they have very specific purposes.

- First extend the dart apex along the centre fold line by 3cm (about 1 1/8 inch). We’ll call this line 1. This should be your centre bust. Mark this point.
- Next draw a line from this point to your armsyce, about 1/3 of the way in. (this is line 2)
- Draw a line down from your centre bust straight over to the side seam(line 3)
- Draw a line perpendicular to grainline about 1/2 way down the dart This line (4) should hit the Line 1 and edge of the pattern.
CUT & OVERLAP
The basic idea is that we’re going to slash along these lines to overlap our pattern to remove the extra room we don’t need.

Cut Line 1 from the bottom to the centre bust, then along Line 2 armscye, making sure not to cut completely through the pattern paper at the armscye. We need to leave a little bit so that we can use it as a hinge.

Next cut Line 3 from the side seam towards the centre bust. Do not cut completely through the pattern paper at the centre bust. Once again, we want to leave a bit of paper to use as a hinge.


Now we want to overlap the slash lines by the amount of our SBA. Keep them parallel along the grainline. I’m doing 1/2″ SBA for this example. An easy way to keep it parallel is to draw a line on the right side of the cut, and then you can easily line up the left side. (ps – this will also cause slash line 3 to overlap).
Tape in place above line 4 (we’re still going to slash there).


Now you’ll see that the centre front is longer than the rest of the pattern. So cut all the way through line 4, and move up, overlapping, so that the waistline is even. Tape in place.


Now re-draw your new smaller dart. Remember, your dart apex point is going to be hidden under your overlapped pieces. So re-mark it where you can see it. Your dart point is 3 cm (1 1/8 inch) below that. Re-draw the dart legs to this point. Trim any excess paper on the edge.


Ok, so now your side seam is actually going to be a little bit shorter (thanks to line 3 overlapping). Darling Ranges already is already a shorter/high waist bodice. So a little bit shorter may not really make much difference to you. If it doesn’t bother you, then all you need to do is shorten the back bodice too to match. Draw a line perpendicular to the grainline on the back bodice piece. Cut across it, and overlap (keep it even!) so that the side seam matches up with the front side seam. Tape in place.
Another option, if you really don’t want the bodice any shorter, is to then lengthen the bodice using this tutorial.
LOOKING FOR MORE DARLING RANGES POSTS?
Here’s the full list of Darling Ranges tutorials:
- Project preparation
- Pattern alterations: full bust adjustment
- Pattern alterations: small bust adjustment
- Pattern alterations: lengthen the bodice
- Pattern alterations: raise the neckline
- Pattern alterations: rounded neckline
- Pattern alterations: fishtail hem
- Pattern alterations: add darts to the back bodice pattern piece
- Sewing & construction: Bodice & darts
- Sewing & construction: Skirt & pockets
- Sewing & construction: Attaching the skirt & bodice
- Sewing & construction: Placket & Neckline
- Sewing & construction: Sleeveless version
- Sewing & construction: Attaching the sleeves
- Sewing & construction: Hemming
- Sewing & construction: Ties & beltloops
- Sewing & construction: Closures
- Sewing and Construction: Sleeveless variation
- Sewing and Construction: Dartless Versions (B & C)
We absolutely love seeing what you make, so don’t forget to tag your creations with #MNdarlingranges and @megannielsenpatterns if sharing on social media.
Don’t have the pattern yet?
