Hot air balloons floating over sandy mountains in Turkey during sunset.

Editor's Pick | Most Popular | Market Place

Royal Mail Parcel Sizes and Weight Guide

You might be wondering, is there a size limit on royal mail parcels? Fortunately, we’ve broken down everything you need to know about Royal Mail parcel sizes and guidelines!

3 July 2026

Author: Parcel2Go.com

What Are the Royal Mail Parcel Sizes?

Royal Mail offers a range of parcel sizes for your individual needs:

  • Letters

  • Large Letters

  • Small Parcels

  • Medium Parcels

  • Tubes/Rolls

  • Parcelforce Parcels

  • Parcelforce Large Parcels

Royal Mail Large Letter Size Explained

Royal Mail offers letter delivery in two sizes, Letters and Large Letters. Large Letters are ideal for items or letters that are slim, but larger than the average letter, and heavier. 

You might have an item that you’d deem a Parcel (like a CD/DVD), but that’s a lot smaller, and lighter, than the Small Parcels category. If that’s the case, check your item against the Large Letter guidelines below!

Large Letter Guidelines:

  • Not exceeding Length 35.3cm

  • Not exceeding Width 25cm

  • Thickness up to and including 2.5cm

  • 750g weight limit (except UK Tracked purchased online, which has a 1kg limit)

You can get your letter checked for weight at your local post office.

Small Parcel, Medium Parcel and Large Parcel Sizes

Royal Mail also offers shipping for Small Parcels, Medium Parcels, and Tubes/Rolls. You can ship Large Parcels with Parcelforce, through Royal Mail. 

Small Parcel Guidelines:

  • Not exceeding Length 45cm

  • Not exceeding Width 35cm

  • Not exceeding Depth 16cm

  • 2kg weight limit

Medium Parcel Guidelines:

  • Not exceeding Length 61cm

  • Not exceeding Width 46cm

  • Not exceeding Depth 46cm

  • 20kg weight limit

*Large Parcel (Parcelforce) Guidelines:

Parcelforce Parcels:

  • Not exceeding Length 1.5m

  • Not exceeding 3m Length and Girth combined

  • 30kg weight limit

Parcelforce Large Parcels:

  • Not exceeding Length 2.5m

  • Not exceeding 4m Length and Girth combined

  • 30kg weight limit

*Larger items are welcome on our Parcelforce Express48 large services that allows up to maximum length of 250cm and length and girth combined of 400cm)

Tubes/Rolls Guidelines:

  • For rolled and cylinder-shaped parcels, the length of the item plus twice the diameter must not exceed 104cm

  • The greatest dimension must be no more than 90cm

Please note: The maximum weight limit for Special Delivery Guaranteed by 1pm® items is 20kg, and for Special Delivery Guaranteed by 9am® it’s 2kg.

Do Royal Mail Accept Heavy Parcels?

Royal Mail accepts parcels up to 30kg in weight through their Parcelforce services, classing them as a Heavy Parcel courier!

When shipping a heavy parcel it is important to choose sturdy packaging to ensure the safety of your item/s during transit. Heavy Parcel services, like Parcelforce Worldwide Express48, often offer a collection service; this is a great option when sending something too heavy to lift, as the courier will come right to your doorstep.

For more information on shipping Heavy Parcels, check out our Heavy Parcels services page.

How to Package a Parcel for Shipping with Royal Mail

Royal Mail offers plenty of tips and tricks to keep your parcels safe throughout the delivery process, so you can be sure you’ve taken the best care of your items.

=Tips & Tricks:

  • Use padded envelopes for sharp edges or odd shapes.

  • Use sturdy containers that are strong enough for your objects.

  • Cushion containers with material like bubble-wrap or polystyrene chips.

  • Seal securely with nylon or vinyl tape along all edges and openings. 

  • Use a FRAGILE sticker, if necessary. 

For more advice on labelling and packaging with Royal Mail, visit their website.

How To Measure Your Parcel Correctly

What is the Length and Girth of a parcel?

The Length of a parcel is always its longest side. The Girth of a parcel is the four shortest sides added together.

How do you calculate the girth of irregularly shaped parcels?

When sending a parcel of an irregular shape, you measure based on the smallest cubic box shape they could fit into. So, measure the Width and Height of the parcel between the widest points. The Length is always the longest measurement, regardless of the orientation of the t is Length and Girth combined?

To calculate for ‘Length and Girth combined’ measurements, simply add the Girth and Length together.

How To Measure for International Delivery

When measuring for International Delivery, you’ll want to calculate the Volumetric Weight of your parcel.

Luckily, Parcel2Go has an easy-to-use Volume Calculator to make shipping overseas as hassle-free as possible!

Please Note: Our Volume Calculator is currently only available for Parcelforce (through Royal Mail) services.

Are There Size Limitations for International Shipments?

International shipments do require senders to follow alternate guidelines. You can check what size category your parcel fits under on the Royal Mail size guide.