Britons have just twelve days to apply for shares in Royal Mail, starting from today.
The share sale, at a price between 260p and 330p, comes as ministers revealed the business would float on the stock market in October.
By comparison, a first class stamp costs 60p and a second-class stamp costs 50p. Royal Mail confirmed that the price of first and second class stamps is set to rise in line with RPI inflation over each of the next three years.
The sale would come as the Communication Workers Union is set to decide whether to launch days after the stock market flotation.
The sell-off would see Royal Mail given a market valuation of up to £3.3 billion. Individuals have a deadline of October 8 to apply for shares, with a market debut set for October 11 and the business to trade unconditionally on October 15.
CWU members are beginning today to vote on whether to take industrial action in opposition to the plan, with the ballot set to conclude mid-October.
CWU general secretary Billy Hayes said: "It seems remarkable that the prospectus is being issued on the same day that postal workers are being sent ballot papers for strike action."
"Royal Mail is profitable and can continue to be successful in the public sector. The sale is driven by political dogma, not economic necessity, and postal workers and the CWU will continue to fight to save services as well as defend their terms and conditions."
Ministers said in a statement that 10% of the shares would be given to around 150,000 "eligible UK-based Royal Mail employees". The coalition plans to sell between 40.1% and 52.2% of the Royal Mail.
Business Secretary Vince Cable said: "This will give Royal Mail access to the private capital it needs to modernise, as envisaged under successive governments and enshrined in law by Parliament two years ago."
Pre-election economy debate April 15, 2010
Two things you may not believe. 1. Nick Clegg, for one brief, fleeting and glorious moment, was really popular. His performance in this debate gave a massive boost to the Lib Dems in the polls and gave the whole race a kick up the behind. 2. Clegg and Cameron were rivals <em>before</em> they were in a coalition together.
Cameron welcomes Clegg to Downing Street May 12, 2010
Imagine you live in a house that's ok, not great, just ok. Now imagine you have this "mate", who you don't really like but you've got to hang round with him because your mates are mates with his mates and your wives get on, that kind of thing. Now imagine that this "mate" that you secretly can't stand has a really, <em>really</em>, nice house that you would absolutely love and he invites you round. I'm pretty sure that's how Clegg felt here.
The Downing Street Rose Garden May 12, 2010
Cameron once called Clegg his favourite joke. Ouch. Obviously that came back to haunt him pretty quick. The funniest thing about this clip though isn't the joke, it's the harrowing and completely un-heart-felt cry of "come back!" from Cameron.
Birmingham Mar 24, 2011
Without the patience to wait for the seven-year-itch, Cameron and Clegg instead let 11 months pass before letting the cracks appear. After a rather heated debate, Clegg could be heard commenting to Cameron that if they carried on like this they wouldn't have anything left to argue about.
Leveson Inquiry November 29, 2012
In a hugely symbolic move, Clegg insisted on making a separate statement on the findings of the Leveson Inquiry into press standards. Although the Government insisted it did not represent "a massive split or disagreement", few could fail to see the significance.
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