If you regularly send products through the post, postage costs can quickly become one of your biggest business expenses. Whether you're shipping subscription packs, books, stationery, beauty products, health and wellness items or other ecommerce orders, choosing the right large letter packaging can make a significant difference to your shipping costs.
Today, sending products as a Royal Mail Large Letter is second nature for many businesses. But it wasn't always that way.
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How Pricing in Proportion Changed Packaging Forever
20 years ago, Royal Mail announced one of the biggest changes to its pricing structure with the introduction of Pricing in Proportion (PiP).
Before PiP, postage prices were based primarily on the weight of an item. As long as a package fell within the weight limits, the type of packaging made relatively little difference. Bubble mailers became the packaging of choice for books, DVDs, CDs, stationery and many other products because they provided cushioning, were inexpensive and satisfied the postal system of the time.
Everything changed when Royal Mail introduced Pricing in Proportion in 2006.
For the first time, the size and thickness of a package became just as important as its weight. Instead of charging solely by weight, Royal Mail created new pricing bands based on a package's dimensions, including the introduction of the Large Letter category.
Businesses suddenly had to think differently about packaging.
Why Bubble Mailers Fell Out of Favour
One of the biggest casualties of Pricing in Proportion was the traditional bubble mailer.
Although bubble mailers provided excellent protection, the padded lining added unnecessary bulk. Many products that would otherwise have qualified as a Large Letter became just a few millimetres too thick, preventing them from passing through Royal Mail's 25mm Large Letter gauge.
Instead of benefiting from the lower Large Letter postage rate, these items were reclassified as Small Parcels, increasing mailing costs considerably.
Almost overnight, businesses began replacing bulky bubble mailers with slimmer packaging solutions that protected products without adding unnecessary thickness. Rigid board envelopes, flatpacks and adjustable book wraps quickly became the preferred choice because they helped businesses stay within Royal Mail's Large Letter limits while still providing excellent protection.
More than two decades later, those principles remain just as relevant for today's ecommerce and subscription businesses.
What Is a Royal Mail Large Letter?
To qualify as a Royal Mail Large Letter, your packaged item must not exceed:
- 353mm x 250mm x 25mm
- 750g maximum weight
Staying within these limits allows you to benefit from significantly lower postage costs than sending a parcel.
Current Royal Mail Large Letter Prices
| Weight | 1st Class | 2nd Class |
|---|---|---|
| Up to 100g | £3.20 | £1.55 |
| Up to 250g | £3.30 | £1.90 |
| Up to 500g | £3.30 | £2.40 |
| Up to 750g | £3.30 | £2.70 |
If your package exceeds the Large Letter dimensions, it becomes a Small Parcel, with prices starting from:
- £5.15 (1st Class)
- £3.95 (2nd Class)
For businesses dispatching hundreds or thousands of orders each year, ensuring products qualify as Large Letters can generate substantial savings.
It's also worth remembering that if insufficient postage is applied because a package exceeds the permitted dimensions, Royal Mail may charge the recipient the outstanding postage along with a handling fee. That's not the customer experience any business wants to create.
Why Large Letter Packaging Matters
Without packaging that's designed around Royal Mail's dimensions, businesses often find themselves:
- Measuring every order individually.
- Paying higher parcel rates to avoid the risk of underpaying postage.
- Spending unnecessary time checking dimensions.
- Missing opportunities to reduce fulfilment costs.
Purpose-designed large letter packaging removes the guesswork, helping products consistently qualify for the correct postal category while remaining well protected.
Large Letter Packaging from Lil Packaging
At Lil Packaging, we've been helping businesses adapt to the demands of Pricing in Proportion for many years.
Our range has been designed to help ecommerce businesses and subscription brands maximise the benefits of Royal Mail's Large Letter service by combining robust protection with slim, letterbox-friendly designs.
Whether you're shipping subscription packs, books, stationery, beauty products, health and wellness items, clothing accessories, electronics or other ecommerce products, our packaging helps you protect your products while keeping postage costs under control.
Lil A3 Envelope
Our 1.8mm thick rigid A3 envelope provides a snug, professional fit while remaining letterbox friendly. Ideal for subscription packs, magazines, catalogues, documents, prints and other slim products.
Lil C4max Large Letter Cardboard Postal Box
Trust in the durability of our C4max cardboard postal box to provide reliable protection for your products. Whether you're shipping delicate crafts or small gadgets, this box offers excellent safeguarding against potential damages during transit.
Optimal Size: With dimensions of 32x22x2.5cm, this box offers a versatile and space-efficient size for various items. Its well-designed dimensions allow for secure packaging, reducing the risk of shifting during shipping.
Lil C3 Bukwrap
Featuring adjustable depth creases, the C3 Bukwrap accommodates products of varying thicknesses while maintaining excellent protection. Perfect for book subscriptions, beauty and wellness products, stationery subscriptions, multiple-item orders and a wide range of ecommerce shipments.
Lil Letterbox Wrap
Designed and manufactured specifically for refurbished mobile phones and small electronics, our latest Large Letter compliant and letterbox friendly Mobile Phone Wrap is 30% lighter, 2x faster to pack, has 6 layers of corrugated protection and is 30% cheaper than comparable mobile phone mailers.
A Smart Choice for Subscription Brands
Subscription businesses are among the biggest beneficiaries of large letter packaging.
Saving even a small amount on each monthly shipment for example, sending specialist coffee like our customers Exhale Coffee or sanitary wear like Wuka can translate into thousands of pounds over the course of a year. At the same time, Large Letter packaging often allows products to be delivered straight through the customer's letterbox, reducing missed deliveries and improving the overall customer experience.
Using packaging that's specifically designed around Royal Mail's Large Letter dimensions helps subscription brands:
- Reduce postage costs.
- Increase packing efficiency.
- Protect products in transit.
- Improve the customer experience.
- Maximise the savings created by Royal Mail's Pricing in Proportion system.
Twenty Years On...
Twenty years after Pricing in Proportion transformed the postal industry, the same principle still applies: the right packaging can have a direct impact on your shipping costs.
At Lil Packaging, our range of large letter packaging has been developed to help ecommerce retailers and subscription brands make the most of Royal Mail's Large Letter service, protecting both their products and their profits.
Explore our range of large letter packaging and discover how choosing the right packaging can reduce postage costs, improve packing efficiency and help every shipment go further.