Large Parcel Boxes & Mailers

Our Large Parcel range covers cardboard boxes, poly mailers, and heavy-duty packaging designed for bulky or oversized shipments that require Royal Mail's Large Parcel service (combined length and girth up to 3m, up to 20kg). This range is ideal for businesses shipping oversized homeware, multi-item bundles, large electronics, and bulk B2B orders. Choose from heavy-duty double-wall corrugated boxes for maximum protection during longer or rougher transit, and extra-large poly mailers for bulkier soft goods and apparel bundles. For smaller items, browse our Medium Parcel and Small Parcel packaging, or visit our postal sizes guide to compare dimensions and find the most cost-effective option.