How To Custom Underwear Sizes For Your Brand?

When a brand first starts developing lingerie, sizing may seem fairly simple. It can be tempting to use several common market sizes and move on. But once sampling and orders begin, practical questions quickly come up: Which sizes should be produced in larger quantities? Which sizes can start with smaller quantities? If a new style is introduced later, can the existing size system still be used? Small decisions like these can easily turn into inventory pressure and extra production costs if they are not handled properly. Custom lingerie sizing is not simply about copying a size chart. The sizing system needs to match the target customers, product range, and sales plans so future product development becomes easier.

How Should a Brand Plan Lingerie Sizes for Its First Product?

A new lingerie brand does not necessarily need to launch with a very wide size range. Initial orders are often limited, and dividing the quantity evenly across every size can create an awkward situation: popular sizes sell out quickly while slower-moving sizes remain in stock. A more practical approach is to identify the target customers and main sales market first, then decide which sizes should be included in the first production run while leaving room to expand the range later.

Another advantage of this approach is that the entire size system does not have to be fixed from day one. If a particular size becomes especially popular, production quantities can be increased. If a collection attracts a different customer group, its size range can be adjusted separately. As the brand grows, the lingerie size system can gradually improve based on real sales performance.

What Information Should a Brand Provide to the Factory for Custom Lingerie Sizing?

Once product development gets underway, problems between brands and factories are not always caused by a lack of experience. More often, the information each team has is simply different. Designers may be working from style drawings, purchasing teams may be looking at order details, while the factory works from production files. If the size specifications are changed during development but the documents are not updated, it can easily become a situation where the brand is talking about one number while the factory is working with another. Keeping the information organized from the beginning makes communication much easier later.

• If the brand already has its own sizing rules, these can be provided directly to the factory. New brands should clearly state which sizes they plan to sell in the first production run.
• List all sizes planned for the initial production and clearly mark any sizes that will not be produced for the time being.
• Brands with previous sales experience can organize common customer feedback about sizing issues and share it with the development team.
• If a collection includes several styles, clearly indicate which styles can use the same sizing system and which ones require separate adjustments.

The information does not need to be overly complicated. The key is to keep it complete and organized. After sample revisions, the final confirmed sizes should be updated promptly, and outdated files should not continue to be used for production. This allows the factory to quickly identify which version has been officially approved.

How Should Lingerie Sizes Be Confirmed After Sampling? Do Not Check Just One Sample

At the sampling stage, a brand should not judge the entire size range by looking at just one sample. One size may fit well while another size shows unexpected problems. What really matters is whether the overall sizing progression remains consistent as the product moves from smaller to larger sizes, without obvious jumps or irregularities.

• Check the core sizes planned for the first production together instead of using only the middle size to represent the entire range.
• Look at whether the progression between neighboring sizes feels natural and avoid situations where the difference is very small between some sizes but suddenly becomes much larger later.
• After sample revisions, record the final confirmed measurements again and use the approved version for bulk production.
• If the fabric, trims, or design are changed later, do not automatically continue using the original sizing. It is better to confirm the sizes again.

Once the samples are approved, keep the final production information properly organized. This makes future development of the same product series much easier. New styles can refer to proven base specifications and then make small adjustments for the specific design, instead of starting the entire process from scratch every time. For brands developing lingerie over the long term, this can save a considerable amount of time.

How Can a Brand Move Custom Lingerie Sizing Smoothly Into Bulk Production?

Once the sizes are finalized, the next step is making sure the approved numbers are actually carried into production. Patterns, cutting files, production orders, and sample records should all use the same final specifications. If the sizing has been revised several times but an outdated file is still used during bulk production, problems can appear even when the earlier development work was done carefully.

For new brands, it can be helpful to manage sizing, style information, and sample approval within the same workflow. This makes it easier for the factory to distinguish between information that has already been approved and details that still need revision, while reducing the time spent searching through old files.

CATONIE can participate in lingerie size development based on a brand's design concept and product requirements, while coordinating sizing, patterns, fabrics, samples, and OEM/ODM production. Brands that already have a tech pack can provide their existing files directly. For brands still in the early development stage, the process can start with the target market and initial product range, followed by step-by-step sizing confirmation.

Custom lingerie sizing is not about making the system as complicated as possible. It needs to be practical, easy to communicate, and suitable for production. Deciding which sizes to make in the first batch, confirming samples, and clearly identifying the final approved version can prevent many problems during bulk manufacturing. As the brand gains more product experience, proven sizes can be retained and used for future development, making new collections easier to launch.