Royal Mail and Parcelforce Parcel Size Guide
5 June, 2026
Updated June 2026
In this guide, you’ll find all the essential details on Royal Mail parcel sizes, regulations, and weight limits for 2026. For eCommerce businesses shipping anything from cosmetics and apparel to boxed homeware and bulkier retail stock, knowing the right size category keeps deliveries moving and costs predictable.
Royal Mail categorises items across letters, small parcels, medium parcels and tubes, with Parcelforce Worldwide handling anything larger or heavier. Each category has its own dimensions and weight limits, so we’ve put this guide together to help eCommerce businesses pick the right size for your deliveries.
Royal Mail Letters
Small letters: used for small, lightweight items. A standard letter must not exceed 24 cm x 16.5 cm x 0.5 cm in size and 100 g in weight. First and second-class letters share the same size and weight limits.
Examples: personal letters, greetings cards, postcards, and everyday items such as bills or invoices.
Large letters: designed for bulkier or thicker flat items. They can measure up to 35.3 cm x 25 cm x 2.5 cm and weigh up to 750g.
Examples: A4 documents, certificates, magazines, brochures, CDs or DVDs in cases, and larger greeting cards. It can also be used for slim books or informational booklets.
Royal Mail Parcels
Small parcels: suitable for compact but heavier or more durable items. These can be up to 45 cm x 35 cm x 16 cm in size and weigh up to 2 kg.
Examples: mobile phones, portable speakers, headphones, books, cosmetics, skincare products, and small clothing items such as shoes or folded garments.
Medium parcels: for larger and heavier items, with maximum dimensions of 61 cm x 46 cm x 46 cm and a weight limit of 20 kg.
Examples: gift packages, multiple clothing items, boxed shoes, kitchen appliances such as kettles or toasters, and other medium-sized household or electronic goods.
Tubes: used for long, rolled items such as posters or artwork. They can weigh up to 2 kg, with a maximum length of 90 cm, and a combined length plus twice the diameter not exceeding 104 cm.
Examples: posters, canvas prints, architectural drawings, blueprints, and rolled documents.
Parcelforce Parcels
Parcelforce parcels: typically reach up to 1.5 m in length and weigh up to 30 kg, depending on the service.
Examples: furniture, kitchen appliances, boxed stock, and larger retail items.
Large Parcelforce Parcels: can be up to 2.5 m in length and 30 kg in weight.
Examples: large furniture such as desks or shelving units, white goods like washing machines, and bulky industrial or trade equipment.
Why It’s Important to Use the Correct Parcel Sizes
Knowing the correct Royal Mail parcel size before sending an item can save you money, prevent delays, and ensure a smoother delivery process.
From 7 April 2026, Royal Mail introduced an £11 correction charge for Tracked 24 and Tracked 48 return items that exceed size or weight limits. This makes accurate measuring more important than ever for Royal Mail delivery performance and cost control.
By carefully measuring your parcels, understanding size categories, and checking current postage rates, you can avoid unnecessary costs and ship with confidence.
If you’re unsure about pricing, you can use the official postage calculator on the Royal Mail website to get real-time estimates based on your parcel’s size, weight, and destination for any Royal Mail post service.
Royal Mail Rules, Regulations and Restrictions Checklist
To ensure your Royal Mail parcel is accepted and delivered without issues, follow these key guidelines:
- Include a barcode, full destination address (with postcode), a UK return address, and a complete sales order.
- Use padded envelopes or mailer bags for sharp or irregularly shaped items.
- Seek approval before using string, strapping, or unconventional packaging.
- Ensure all shipping labels are clear and legible.
- Place one address label on the outside and another inside the parcel.
- Avoid wrapping labels over edges or covering them with tape.
- Use a thermal printer and Royal Mail-approved software for label printing.
- Protect fragile items with adequate cushioning (e.g., bubble wrap, book wrap).
- Ensure items inside the box do not move or touch the sides.
- Seal all edges securely with strong packing tape.
- Clearly mark fragile items with a ‘FRAGILE’ sticker.
- Some services may require items to be weighed individually or sealed in specific packaging.
Certain items are prohibited or restricted when sending via Royal Mail:
- Prohibited items: explosives, flammable substances, and hazardous materials
- Restricted items: alcohol, tobacco, and some perishable goods (especially for international shipping)
Always check the latest guidelines on the Royal Mail official site before sending your parcel to avoid delays or penalties in Royal Mail delivery services.
How ELOVATE Can Help with Your Shipments
ELOVATE works directly with Royal Mail through direct injection, helping streamline your fulfilment process and reduce shipping costs.
With ELOVATE, you benefit from:
- Negotiated lower shipping rates
- Real-time tracking and courier updates via an online portal, including full Royal Mail tracking visibility and insights
- Access to other major UK carriers, including DPD, UPS, Yodel, FedEx, Evri, DHL
Instead of manually tracking Royal Mail processes or juggling different carrier systems, ELOVATE centralises everything, so you always have visibility into shipments and can easily track parcels, making it simple to make smarter fulfilment decisions.
ELOVATE evaluates the pros and cons of each courier and assigns the most suitable option for your business. This includes a multi-courier strategy, allowing you to optimise cost, speed, and reliability, so you can focus on growing your business instead of managing logistics complexity.