• Key features of bubble mailers
• Cushioning and shock absorption: The bubble wrap lining absorbs impacts and protects fragile items from scratches and breakage. In the cited example, laminated kraft and bubble wrap construction provides stiffness and puncture resistance while remaining lightweight.
• Water‑resistant: The laminated outer layer helps protect against moisture during transit.
• Self‑seal and tamper‑evident: Like poly mailers, bubble mailers usually have a peel‑and‑seal flap for fast packing.
• Multiple sizes: Bubble mailers come in standard sizes (e.g., A/000, C/0, C/1, etc.) that correspond to internal dimensions. For example, a C/0 padded envelope has internal dimensions around 165 mm × 165 mm and can accommodate a single DVD case, while a C/1 envelope (around 180 mm × 235 mm) fits thicker box sets.
• Protective but heavier: The cushioning layer makes bubble mailers heavier and bulkier than poly mailers. That additional thickness can push a shipment into a more expensive postal category.
• Best products for bubble mailers
• Bubble mailers are designed for fragile or breakable items. DVDs, CDs, books, jewellery, small electronics, cosmetics and accessories benefit from the cushioning provided by bubble wrap. The previously cited DVD mailer product states that the inside of the mailer can hold one standard DVD or up to two slim DVD boxes, and the laminated bubble‑wrap construction reduces shipping weight while ensuring the contents remain safe.

Best products for poly mailers

Poly mailers are ideal for soft and durable items such as clothing, textiles, accessories, fabrics, bedding, lightweight shoes and some electronics accessories. They provide enough protection for goods that aren’t fragile or prone to breaking. Retailers often choose poly mailers when they need to ship large volumes economically, when the products aren’t likely to be crushed or damaged by minor impacts, or when packaging needs to stay within Royal Mail’s cheaper Large Letter pricing band (discussed later).

What are bubble mailers?

Bubble mailers – also called bubble‑lined padded envelopes – consist of an outer layer of paper or plastic and an inner layer of bubble wrap. The bubbles provide cushioning to protect delicate items from shocks and punctures. A product listing for DVD bubble mailers notes that the mailer walls are lined with a 3/16‑inch bubble layer; the bubbles retain air to create cushioning and the air cellular lining surrounds the DVD box. The mailers also feature a peel‑and‑seal closure and are water‑resistant.