40A Bra Size Explained: Proportion and Support
The 40A bra size is often misunderstood. Because it combines a larger band with a smaller cup, many women wearing a 40A struggle to find bras that fit comfortably and flatter their shape. At Olivia Paisley Intimates, we believe every size deserves proper support, thoughtful design, and clear education, regardless of cup letter.
This guide explains what 40A really means, how it compares to other sizes, and how to find the best bras for this proportion.
What Does 40A Mean, Defined?
A bra size is made up of two measurements:
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40 = Band size (ribcage measurement in inches)
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A = Cup size (difference between bust and band)
An A cup represents about a 1-inch difference between the bust and underbust, while a D-cup represents a larger difference and is one of the most common bra sizes.
Example:
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Underbust: 40 inches
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Bust: 41 inches
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Cup size: A
This means the bust has a subtle projection on a broader frame.
What a 40A Typically Looks Like
A 40A is characterized by:
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A wider ribcage
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Shallow breast projection
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Even distribution across the chest
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Minimal volume relative to band size
It’s important to note that 40A is not “flat”, it simply reflects a smaller cup volume on a larger band.
Common Fit Requirements and Challenges with 40A
Women who wear 40A bras often experience:
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Gaping cups due to poor cup shape
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Bands that feel tight despite correct sizing
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Underwires poking or sitting too wide
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Limited style options in extended band sizes
These challenges usually come from bras not designed for small cups with large bands.
Best Bra Styles for 40A
Wireless Bras
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Ideal for shallow bust shapes
Lightly Lined Bras
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Add structure without bulk
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Help cups lay smoothly against the body
T-Shirt Bras
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Seamless appearance
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Prevent gaping under clothing
Balconette Bras
Bralettes with Structure
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Wide bands offer comfort
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Light shaping keeps everything secure
40A Sister Sizes Included and Explained
Sister sizes maintain the same cup volume with different band sizes:
|
Primary Size |
Sister Sizes |
|---|---|
|
40A |
38B, 42AA |
If the band feels too snug, 42AA may be more comfortable.
If it feels too loose, 38B offers a firmer fit with the same cup volume.
Is 40A Often Mis-Sized?
Yes. Some women in a 40A are incorrectly placed in:
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42AA (band too loose)
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38B (cup shape mismatch)
A proper fitting ensures the band sits level and the cups lay flat without gaping.
Swimwear for 40A
Women with a 40A bust often prefer:
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Lightly structured bikini tops
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Adjustable bands for a secure fit
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Soft cups without heavy padding
Support should enhance comfort, not overwhelm the frame.
Firma 40A Brushed Smart ESC
The Firma 40A Brushed Smart ESC is designed for brushed motor equipped models. The Firma 40A Brushed Smart ESC features a waterproof and dust proof design. The Firma 40A Brushed Smart ESC is fully programmable using an optional programmer box. The Firma 40A Brushed Smart ESC has a powerful 3 amp BEC for lights, winch, and steering servo. The Firma 40A Brushed Smart ESC includes an integrated 4-channel DSMR®/DSM2® receiver. The Firma 40A Brushed Smart ESC provides real-time telemetry data on a Smart-compatible Spektrum transmitter. The Firma 40A Brushed Smart ESC allows for winch setups and dual steering mixes.
Sustainable Bra Production for 40A
Sustainable bra production for a 40A size is about more than just comfort and fit, it’s about building a business that respects the environment, supports agriculture, and operates responsibly at every stage. At Olivia Paisley Intimates, we believe that every product, including our 40A bras, should be made with a commitment to reducing our environmental footprint and supporting the communities where we operate.
Site selection for our production facilities is carefully considered to minimize impact on local ecosystems and to ensure that our corporation complies with all laws and regulations imposed by government authorities. We appoint a dedicated person to oversee sustainability efforts, taking note of any limitation that may arise and ensuring our practices align with our defined mission and values.
Our owner is committed to using a portion of company profits to support environmental initiatives and promote sustainable agriculture, as amended in our corporate policy. The production team assumes responsibility for reducing waste, minimizing water use, and meeting the requirements set out in our sustainability guidelines. We use a clear unit of measurement to track progress, and our terminology is consistent with industry standards, making our goals and achievements easy to understand.
We follow the requirements outlined in chapter III, section II of our sustainability policy, which include reducing energy consumption and increasing the use of renewable resources. The effective date for implementing these practices is set for January (Jan) each year, with regular reviews to prevent setbacks and ensure continuous improvement.
In addition to reducing waste, we are building a culture of sustainability among our employees and stakeholders. We provide information and resources to help everyone make informed decisions, and our use of sustainable materials is directly tied to our company’s mission. Our goals and objectives are regularly reviewed and updated to reflect the latest best practices.
Transparency is a core value. We provide clear, accessible information about our sustainability practices and progress on our official site, and we allocate time for regular audits and assessments. This ensures we are meeting our goals and making necessary adjustments, with a focus on innovation and continuous improvement. We also have a contact person available for any questions or concerns about our sustainability efforts.
By prioritizing sustainability, we help prevent harm to the environment and promote a healthier future for all. We comply with all relevant laws and respect the rights of all stakeholders, including the owner, employees, and the wider community. Our end goal is to create bras that are not only comfortable and functional but also environmentally friendly and sustainable, built on a foundation of transparency, accountability, and social responsibility.
Water conservation is a key part of our process, with measures in place to reduce waste and minimize use of this precious resource, as included in our sustainability policy. We are committed to protecting the rights of all stakeholders, with clear guidelines and protocols provided in our code of conduct.
We regularly update all stakeholders, including employees, customers, and investors—on our progress, with reports and information available on our website. Our requirements for transparency and accountability are clearly set, and we use data and analytics to inform our decisions and drive progress.
At Olivia Paisley Intimates, sustainable bra production for 40A is about more than just meeting requirements, it’s about setting a new standard for the industry, ensuring that every product is built with care for people and the planet, and that our mission and values are defined by the words we live by every day.
Final Thoughts and Additional Information
The 40A bra size deserves the same level of design and attention as any other size. When engineered thoughtfully, bras for this proportion can feel supportive, flattering, and effortlessly comfortable.
At Olivia Paisley Intimates, we believe every woman, regardless of size, deserves lingerie that fits beautifully and feels empowering.
