Ever tried on the same bra size in two different brands and thought… how can both of these be right?
You are not imagining it — and you are definitely not alone.

It is completely normal to wear different bra sizes in different brands. Bra sizing is far from universal, and several factors influence how a bra fits from one brand to the next. Understanding why this happens can save you frustration and help you find bras that actually feel good on your body.

Let’s break it down.

There Is No Universal Bra Sizing Standard

Unlike clothing, bra sizing is not fully standardised across brands. Each lingerie brand uses its own fit models, design philosophy, and sizing guidelines. That means a 34DD in one brand may fit very differently in another.

Some brands scale cups and bands more generously, while others design for a firmer or more relaxed fit. This is why the same size on the label does not always mean the same fit on your body.

Country of Origin Matters More Than You Think

Bra sizing also varies depending on where the brand is based.

UK, US, and European brands all use different sizing systems. Even if the size label looks the same, the proportions may not be.

UK brands often focus on fuller bust support
US brands can run slightly different in cup depth
European brands usually use metric measurements rather than inches

This is why knowing whether a brand follows UK sizing (like Tutti Rouge) makes a big difference when choosing your size.

Every Brand Designs for a Different Body Shape

Brands design bras based on their ideal fit model. This model influences cup depth, wire width, strap placement, and overall shape.

If your body shape differs from that model, you may need a different size or style within that brand to get the best fit. This is not a flaw in your body — it is simply how lingerie is designed.

Bra Style Changes the Fit Too

Even within the same brand, different styles can fit very differently.

A plunge bra may feel tighter in the cup
A balconette may give more lift but less coverage
A full coverage bra may feel more secure but slightly firmer

This means you might be one size in a plunge bra and another in a full coverage style — and both can be correct.

Fabric and Stretch Play a Huge Role

The materials used in a bra can dramatically affect fit.

Stretchy fabrics like elastane or mesh may allow more flexibility
Firm lace or satin may feel tighter and need a different size
Bands with stronger elastic may feel more supportive but snug

This is why two bras in the same size can feel completely different on your body.

Manufacturing and Wear Can Affect Fit

Even bras from the same brand can vary slightly due to manufacturing processes. Small differences in fabric cutting or stitching can change how a bra feels.

On top of that, older bras naturally stretch over time. If you are comparing a new bra to one you have worn for months or years, it may feel like your size has changed when really the bra has.

Why Trying Sister Sizes Can Be a Game Changer

If a bra almost fits but not quite, sister sizes can help.

For example
If a 34C feels too tight in the band, try a 36B
If a 36D feels too loose, try a 34DD

Sister sizing allows you to adjust band and cup proportionally to find a better fit without changing the overall breast volume.

How to Find the Best Fit Across Different Brands

To make bra shopping easier, try these expert tips:

Get professionally fitted whenever possible
Always check brand specific size guides
Read reviews from people with similar body shapes
Be open to trying different sizes and styles
Remember that comfort and support matter more than the label

At Tutti Rouge, we design with real bodies in mind and always recommend choosing the size that feels best on your body — not the one you think you should be.

Different Brands Mean Different Sizes And That’s Okay

Wearing different bra sizes across brands does not mean your body has changed or that you are wearing the wrong size. It simply reflects how bras are designed differently from brand to brand.

The goal is not a number or a letter — it is comfort, support, and confidence.

Find Your Perfect Fit with Tutti Rouge

Our lingerie is designed to support fuller busts, celebrate curves, and make you feel amazing from the inside out. If you are unsure about your size, we are always here to help.

👉 Explore Tutti Rouge Bras
👉 Shop Bralettes and Supportive Styles
👉 Book a Tutti Bra Fitting