Pricing in Proportion

Royal Mail introduced a new pricing structure for Inland Letter Services starting on 21 August 2006. Called Pricing in Proportion, or PiP for short, it is intended to reflect the higher costs of processing larger items of mail. For most users, it means higher postage costs for many items, not to mention the added complexity.

PiP updates are now available for ALL MH Series Postal Scales manufactured by Cherlyn.

The new PiP pricing structure means that charges for Inland letters is based on Size as well as Weight. The current Inland First & Second Class Letter Services have been divided into three size categories, summarized below:

Letters:  These must be smaller than 240mm x 165mm x 5mm and weigh less than 100g.

Large Letters:  Can exceed the limits above, but must be smaller than 353mm x 250mm x 25mm and weigh less than 750g.

Packets:  Anything larger or heavier than the limits for Large Letters, up to a maximum weight of 30kg for First Class, and up to 1kg for Second Class.

Royal Mail has introduced PiP to help bring its pricing structure more into line with its costs. It believes that different formats of mail incur significantly different handling costs. For instance Letters, which will be cheapest, can be speedily processed by automated machinery. Packets, on the other hand, are the most expensive because they require manual handling. This pricing method is common in Europe.

A cardboard template Size Guide is available from Royal Mail to help you determine which size category items fall into. You then need to weigh the item and refer to the Royal Mail rate tables to work out the price. If you have a Cherlyn manufactured Postal Scale, this will be able to carry out the weigh/price calculation for you.

Note that even after you have sized the item, it may still be forced into a larger size category because of its weight. Price computation on the Cherlyn Scales will automatically take this into account, without you having to change your size selection on the Scale. You will immediately be ready to weigh the next item (in the same size category) without having to do anything to the Scale. 

The development team at Cherlyn have produced updated Rate Chips which will allow ALL Cherlyn MH Series Postal Scales - even the oldest models - the facility to handle Pricing in Proportion. There will be easy key selection of item size, and then weighing as normal.

So the message is to SIZE IT then simply WEIGH IT on your Cherlyn Postal Scale. Click here for details of the current range of Cherlyn Postal Scales.

Cherlyn manufactured Postal Scales that have PiP implemented:

Cherlyn Postal Scales:  Models  MH520, MH530, MH730.

Ascom & Ascom-Hasler Postal Scales:  MH520, MH530, MH540, MH730, MH120, MH121, MH122, MH140, MH141, MH142, MH340, MH341, MH342.

Hasler (GB) & Mailtronic Postal Scales:  MH14, MH18, MH19, MH33, MH34, MH30, MHX30, MH31, MHX31.

Frequently Asked Questions:
Sounds complicated! - How do I work out the new postage costs?
Determine which category the item is in by size, select it on your Cherlyn Postal Scale, then weigh. The Postal Scale will give you the correct Postage Costs, and even include the Franking Discount if appropriate.
Will I be able to use my current Cherlyn Postal Scales with PiP?
Yes, ALL Postal Scales manufactured by Cherlyn can easily be updated for PiP, including those branded as Ascom, Hasler & Mailtronic.

How do I update my Postal Scales?

As your scales use a rate chip (often called a PROM) to determine the correct postage, you will just need to replace the rate chip with a new one that is programmed for the PiP pricing structure – exactly like a regular price change. All Rate Chips supplied after August 2006 will include PiP.

Are there any Cherlyn produced Postal Scales that cannot be upgraded for PiP?

No - even very old models like the MH18 and MH33 can be updated to give the correct PiP pricing.

What about my Franking Machine?

You will not need to make any changes to your franking machine as a result of PiP implementation.

Will I have to Change the way I handle Post?

You may want to review the way you prepare your mail for posting, as the changes mean you will now need to measure the size and thickness of an item before you weight it.  It will be good practice to sort post into similar sized items before pricing.

How Can I assess the size of an item of post?

You should have received a cardboard template from Royal Mail - which will give you the ability to check the size and thickness of your post. With a little practice you should be able to assess most of your post by eye.

Which Royal Mail Inland Services are NOT be affected by the changes?

Special Delivery and ParcelForce Services are not affected.

Do the changes affect International Services?

No, International Services are NOT be affected by the changes in August 2006.

How do I get Royal Mail’s cardboard templates to size my mail?

You can order additional Size Guides on-line by visiting the Royal Mail website at

How can I save on my postage costs?

One simple way to save money on your postage costs is to simply fold your larger items to fit into a C5 or DL size envelope, you may fall into the cheaper Letter size price band.  If you are producing leaflets or brochures, now is the time to consider the most cost effective formats.

How can I find out more about the tariff structure?

Royal Mail have already published the sizes and an indicative price structure for PiP, you can find it at

I have another question…

If you need more information, or have unanswered questions concerning Pricing in Proportion, you can contact Cherlyn by email to or by phone on (01223) 424169.

Click here to go to see details of the full list of Postal Scales we have produced, for all of which we supply Postal Rate Chips

You can also see details of our range of Post Room Equipment, or go to the Cherlyn Home Page.

© Cherlyn Electronics Limited, 2007