ORDINARY LETTER Thickness: 5mm or less Length: 240mm or less Width: 165mm or less Weight: Less than 100g Cost:32p Old Royal Mail prices

Later this month will see a radical change for anyone posting a letter or parcel in the UK. In our three factboxes we summarise what you need to know about the changes, with all prices given for First Class delivery.

It has been described "as a megadisaster in the making" and the biggest change in the British postal service since the introduction of the first self-adhesive stamp, the Penny Black in 1840.

Under the Pricing in Proportion scheme, the Royal Mail will move from charging for letters and parcels by weight alone, with size now also a factor.

Officials behind the scheme say it is necessary to fairly reflect the cost of carrying items, which is defined as much by size as it is by weight.

It will dramatically change the dynamics of postage. A single sheet of A4 sent through the post unfolded - now in the "Large Letter" category - will cost more than the same letter folded in half.

LARGE LETTER Thickness: 25mm or less Length: 353mm or less Width: 250mm or less Cost: 100g or less - 44p 250g or less - 65p 500g or less - 90p 750g or less - 131p

Critics say posting a letter is a complicated enough business already, and the new rules will make things more complicated.

But the Royal Mail dismisses suggestions that it is likely to increase revenues with the measures, insisting that 85% of post will either stay the same price or be cheaper. The Royal Mail has a number of examples of types of post that will benefit.

• Hardback books. Taking a Harry Potter novel as an example, the Royal Mail says the cost of postage First Class will go down from �2.89 to �2.20
• A typical women's glossy, such as Elle magazine, will go down from �2.69 to �1.31 as it slips into the new Large Letter category
• Slightly weighty letters will benefit under the scheme as the flat First Class postage rate of 32p will apply to envelopes able to contain A5 letters up to 100g as opposed to the previous limit of 60g

PARCEL Thickness: 25mm or more Length: 353mm or more Width: 250mm or more Weight: 750g or more Cost: 100g or less - 100p 250g or less - 127p 500g or less - 170p 750g or less 220p 1kg or less - 270p 1,250g or less: 474p Each additional 250g - +85p

For many parcels up to 1kg in weight, the cost is likely to be reduced.

The exceptions are bulky or odd shaped items which are extremely light. The perfect example would be a poster tube, which will now be considerably more expensive.

But some ordinary letters will fall foul of the new specification that they must not be more than 5mm thick. It means greetings cards featuring humorous badges will now cost 12p more to send.

Independent watchdog Postwatch disputes the Royal Mail's suggestion that 85% of post will be the same cost or cheaper and says the moves will mean confusion and bigger queues in Post Offices.

A prime example of the kind of business whizzkid idea that nobody wants, to be filed alongside the 50 different directory enquiries numbers. I'm sure most of us would prefer an extra couple of pence on postage than to have to deal with this. Also annoyed by the dissimulation involved in claiming that this move won't increase revenue. If there wasn't a financial advantage involved there'd be no point in them doing it. Saying they 'won't increase revenue' is a code for saying that they will decrease costs and therefore increase profits (as opposed to revenues). Long live corporatespeak.
Andy, London, UK

This seems designed to cash in on sales of DVDs and CDs over the Internet as these items are thick but light - probably with the result that free postage will now be a thing of the past. For people like myself who sells items on eBay, it's difficult enough queueing up to post something without having to measure it as well.
Chris Bates, Didcot, UK

This whole idea is pathetic. I used to live in the USA and for 39c (21p) I could send a letter coast to coast. The mailman even collects the post from outside your door every day.
Martin Pope, UK

I am even more confused than ever. Will the Royal Mail be sending everyone in the country a Ruler & a Pair of Scales so that we stand a chance in getting it right.
Mr. T. Short., Forest Hall, Newcastle upon Tyne

I wonder what the banks are going to do? I can't count the number of times I've had a statement through the post which is over 5mm thick, when you include all the rest of the junk they put in the envelope. And what about my cheque book? That's about 5mm on its own.
Robert Irwin, Fareham, Hampshire,UK

Does this mean there will more stamps for each type of letter / parcel. Its hard enought getting through the queues at the post office without having to wait to check is a letter will cost 32p or 49p because there is a badge on the birthday card. Is there any more guarantee of next day deleivery for first class
Nick Farina, Liverpool

I think the introduction of the new scheme is ludicrous. I realise that a similar system is used in parts of Europe - but this is going to result in many more letters being held up because they have not got the right postage on them! Christmas post this year will be horrendous - I think that I had better post everything in October to avoid the post office queues!
L, Hampshire, UK

I can see this being a disaster in the making. Are we supposed to carry around a ruler and a set of scales with us in case we want to send a letter to someone?
Caroline, Sheffield

Working in a postroom for a large company, it's already causing us a massive headache trying to understand the differences between the new and old systems and changing our posting methods to suit the new system. For your average man on the street who posts letters occasionally, this is going to be a nightmare. This will be the most costly blunder in corporate history.
Dewi, Manchester

This all makes sense in principle. The problem is just a logistical one. It must surely be possible to produce a self-service device that will weigh and measure items at the stamp machine so that we don't need to queue up at the post-office counters. That would free up time for staff to deal with more challenging tasks.
Matt, London

I think this is a disgrace - we should all organise a boycott of the post office to show our strong feeling. Bring back the pigeon post!
Jonathon Barrass

Just another reason to not use royal mail, and stick with electronic communications. Who on earth is able to to work all of this out without being at a post office. It's not like getting to the post office is that easy, since they've been shutting them down faster than you can say "rip off postage".
Chris, Cambridge, UK

Is it only 'humorous' badges that will cost more to post? If so will the post office clerk have to open the envelope in order to asses the badges' comedic value?
Grant, Farnham

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