Fantasie Bra Fitting Guide

Finding the right Fantasie bra makes more difference than almost any other thing in your wardrobe. It changes how clothes sit, how comfortable you feel by the end of the day, and whether that expensive top you bought actually looks the way it should.

The problem is that most women are wearing the wrong size. Not by much, but enough to matter. Sizes change over time: with weight, with age, after pregnancy, after surgery. Fantasie recommend getting measured every six months, because weight loss or gain, breastfeeding and menopause can all have an effect.

This guide walks you through how to measure your bra size at home and how to choose the right Fantasie style for your shape. If you would prefer to be measured properly, we offer professional bra fittings at Shirley Allum Boutique in Shaftesbury. Just come in and ask.

What You Need

A soft fabric tape measure and a mirror. That is it. Do this in a well-fitting (non-padded) bra if you have one, or without a bra if not.

Step 1: Measure Your Band Size

Take the tape measure around your ribcage, directly beneath your bust. Keep it snug but not tight. You should be able to breathe normally. Note the measurement in inches.

If the number is even, that is your band size. If the number is odd, round up to the next even number.

28 inches = 28 band / 29 inches = 30 band / 30 inches = 30 band / 31 inches = 32 band

Your band size is the number in your bra size: 32, 34, 36, 38, 40, and so on.

Step 2: Measure Your Bust

Now measure around the fullest part of your bust, keeping the tape parallel to the ground. Do not pull tight. Let the tape sit naturally against you. Note this measurement in inches too.

Step 3: Calculate Your Cup Size

Subtract your band measurement from your bust measurement. The difference gives you your cup size.

1 inch = A cup / 2 inches = B cup / 3 inches = C cup / 4 inches = D cup / 5 inches = DD cup / 6 inches = E cup / 7 inches = F cup / 8 inches = FF cup / 9 inches = G cup / 10 inches = GG cup / 11 inches = H cup / 12 inches = HH cup / 13 inches = J cup / 14 inches = JJ cup / 15 inches = K cup

So if your band measures 34 inches and your bust measures 40 inches, the difference is 6 inches: you are a 34E.

Sister Sizes: When the Fit Is Not Quite Right

Bra sizing is not as fixed as it looks. If your bra fits in the cup but not the band (or vice versa), sister sizing is worth knowing about.

If you go up a band size, go down a cup size to keep the same cup volume: 34E becomes 36DD or 38D. If you go down a band size, go up a cup size: 34E becomes 32F or 30FF.

The cup holds the same volume across these combinations. Only the band firmness changes. This is particularly useful for women in fuller cup sizes where exact band and cup combinations may not always be in stock.

How to Know If Your Bra Actually Fits

Getting the measurements right is a start. But fit is also about how the bra behaves when you are wearing it. Fantasie's fit checklist covers six things to look for: the underband, centre front, cups, underwire, straps, and the all-important swoop and scoop technique.

Fantasie bra fit checklist showing correct fit points

1. The Underband

Your underband does around 80% of the work in a well-fitting bra, so getting this right matters most. It should sit snug and level at the front and back, parallel to the ground. If it rides up at the back, the band is too large or the cups are too small.

2. The Centre Front

The centre front of your bra should sit flat against your chest bone, separating your breast tissue. If it lifts away from your body, this is a sign that the cup is too small.

3. The Cups

The right cup size gives you an even, rounded shape with no spillage over the top or sides. The cups should fully encapsulate your breast tissue, with the underwire sitting completely behind your breast, not on it. If you are spilling out even slightly, go up a cup size.

4. The Underwire

The underwire should extend right behind your breast tissue to prevent bulging and squashing under your arms. If the wire digs in or sits on breast tissue rather than against your ribcage, the cups are too small.

5. The Straps

Straps should stay on your shoulders without digging in. You should be able to slide two fingers underneath comfortably. If your straps are doing all the work, your band is likely too loose. Straps carry far less of the support than most people think.

6. Swoop and Scoop

This is one of the most useful fitting tips Fantasie teach, and it makes an immediate difference. Before you fasten your bra, reach your opposite hand into the cup and scoop all of your breast tissue forward from the back, so it sits comfortably cradled in the cup and in front of the underwire. You may find after doing this that you need to go down a band size and up a cup size. This is very common in women who have never been shown this technique.

A Note on Fuller Cup Sizes

If you measure above a D cup, the general guidance above still applies, but bra style makes a much bigger difference at this end of the range. A full cup bra and a balcony bra will fit very differently on the same woman, even in the same stated size.

Side support construction is something Fantasie specialises in, and it changes how the bra sits and how it feels through the day. It redistributes weight from the straps to the side of the bra, giving a rounder shape and reducing shoulder strain. If you have a fuller bust and have never tried a side support bra, it is worth coming in for a fitting.

We carry Fantasie bras at Shirley Allum from D to K cup and stock the styles that genuinely work for fuller busts. If you are a D cup or above, a fitting with us is worth the time. Style guidance makes a much bigger difference at that end of the range than the measuring itself.

Which Fantasie Style Is Right for You?

Choosing the right bra style is as important as choosing the right size. Here is a guide to the main Fantasie styles we stock and what each one is designed to do.

UW Side Support Bra: The side panel creates forward projection and lift, redistributing the weight of a fuller bust away from the straps. Best for D cup and above. The most recommended Fantasie style at Shirley Allum.

UW Full Cup Bra: Higher coverage at the apex to fully encapsulate the breast. Ideal for those who want maximum support and coverage, particularly in larger cup sizes.

UW Plunge Bra: A lower centre front for a plunging neckline. Works best in smaller cup sizes within the Fantasie range. Good for lower-cut tops and dresses.

UW Padded Half Cup Bra: Less coverage at the top of the cup for a more open neckline. Soft foam padded cups give definition and shape. Called a half cup because of the reduced top coverage compared to other styles.

Fantasie bra shapes explained: side support and full cup bra

UW Moulded Bra: Seamless moulded cups give a smooth, clean line under fitted clothing. No seams means no visible lines. Good for T-shirts and close-fitting tops.

UW Balcony Bra: A straighter neckline across the top cup for a more open look. Wider-set straps. The underwire is deeper for additional coverage and comfort in larger cup sizes.

UW Vertical Seam Bra: Uplift through seam shape. A sheer style in most cases, good for lighter coverage while maintaining structure.

UW Strapless Bra: Detachable fully adjustable multiway straps can be worn over the shoulders or across the back. Stay4Sure gripper elastic gives increased support and hold.

Fantasie bra shapes explained: moulded, balcony, vertical seam and strapless bra

UW High Apex Bra: A bralette style without sacrificing support. The top cup panel lifts to a high apex for additional coverage and shape.

UW Longline Bra: An elongated cradle that extends past the bustline towards the waist, with a deep continuous hook and eye closure for support and a smooth back.

Non-wired Bralette: Non-wired for a comfortable, flexible fit without sacrificing the Fantasie fit philosophy. A good option for those who prefer softer support.

Fantasie bra shapes explained: high apex, longline and non-wired bralette

Professional Bra Fittings at Shirley Allum Boutique

We offer bra fittings in-store at Shirley Allum Boutique on the High Street in Shaftesbury, Dorset. No appointment is needed. Our team will measure you, talk through what is working and what is not with your current bra, and show you styles across our lingerie range that suit your size and shape.

We stock lingerie from Fantasie, Triumph, Charnos, Wacoal, Elomi, Freya and more than twenty other brands, across a size range that runs from 28 back to 48 back and from A cup to K cup. Whatever your size, we will have something that fits.

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Fantasie Bra Fitting FAQs

You need a soft tape measure. First measure around your ribcage directly beneath your bust. This gives your band size. Then measure around the fullest part of your bust. Subtract the first measurement from the second: the difference in inches gives your cup size, starting at A (1 inch difference) up to K (15 inches). For a full step-by-step guide, see the sections above.

Sister sizes are bra sizes that contain the same cup volume but with a different band size. If you go up one band size, go down one cup size: for example, a 34E and a 36DD hold the same cup volume. Sister sizing is useful when a style is not available in your exact size, or when a bra fits the cup but not the band.

A well-fitting bra has a band that sits level around your back, wires that sit completely outside your breast tissue against the ribcage, cups with no spillage or gaps, and a centre front that lies flat against your sternum. The straps should stay on your shoulders without digging in. If the band rides up at the back, the band is too large or the cups are too small.

Shirley Allum Boutique on the High Street in Shaftesbury, Dorset offers professional bra fittings in-store. No appointment is needed. The team stocks bras from more than twenty lingerie brands across sizes from 28A to 48K, including Fantasie, Triumph, Elomi, Wacoal and Freya.

For D cup and above, full cup and side support bras tend to give the most support and the best shape. Side support bras, a speciality of the Fantasie range, redistribute weight away from the straps to reduce shoulder strain and give a rounder, lifted shape. Non-wired styles are also available in fuller cup sizes for those who prefer them. A professional fitting helps identify which style works best for your shape.

Swoop and scoop is a fitting technique where you reach your opposite hand into the cup and scoop all of your breast tissue from the back to the front, so it sits comfortably in the cup and in front of the underwire. It is recommended by Fantasie and often reveals that you need a smaller band and larger cup than you thought. It makes a significant difference to how a bra fits and feels.