For most, it will be their first experience of direct share ownership although many, of course, will promptly sell their shares to invest or spend the cash elsewhere. But for those prepared to take the long-term view, windfall shares could provide the first stepping stone towards building a stock market portfolio. If you fall into this category, you need to give the subject a few minutes thought now, rather than waiting until the envelope lands on the mat.
As Charles Vintcent, a London stockbroker and investment adviser explains: "Most people come into the stock market by accident. Something happens that either gives them some capital, or puts them in the position where they need to make their existing capital work harder, and they come to realise that they should look at investing in shares."
In recent years, he says, many of his new clients have been managers and executives who were made redundant.
"They have often collected some sort of pay-off, and because they have a certain level of expertise can find part-time or consultancy work which gives them a reasonable standard of living," he says. "But they need to make their capital grow to secure a comfortable retirement - and that leads them to the stock market."
Like all private client brokers, Mr Vintcent found himself spending large amounts of time explaining to clients how the market works, what moves it, and how to construct a portfolio. All of which prompted him to write the best-selling guide to investment and share trading: How to be your own Stockbroker.
The book has been followed up by a software package, Cybertrader, which allows investors to analyse share prices, select and manage their own portfolios, track performance and set buy/sell limits, using Stock Exchange closing prices and other information downloaded from the Internet each night. One key feature is the ability to run separate trading and investment accounts, so that you can look for short-term opportunities as well as long-term growth.
Cybertrader's focus contrasts sharply with Infotrade, which offers a broad range of financial services, including will writing, insurance and mortgage quotations as well as stock market investment.
Both programs use a dial-up link to a central database which then updates information on your PC's hard disk.
For those with a speculative bent, the Infotrade service even covers the Ofex trading facility for smaller companies.
And there are links to lots of useful information, including sector averages so you can contrast selected stocks with others in the same way of business, and background material from a variety of sources.
But the big bonus from Infotrade is the direct links to three execution- only brokers - ShareLink, Cater Allen's CityDeal and Brewin Dolphin's Stocktrade service.
Once you have an account with a broker you can place buy and sell orders on-line. The system automatically calculates dividends received and expected, downloading the information by modem, and the new version, to be delivered next week, calculates your capital gains tax position, if any.
The other big enhancement to the system (available from May) will be daily reports of directors' dealings, often a reliable indicator of company prospects.
It's one thing to have the tools, but knowing how to use them - and make money with them - is quite another story. And that's where the private investor often comes unstuck.
One solution is to join forces with a few friends to form an investment club - essentially a group of people who contribute an agreed sum each month and decide together how it should be invested.
There are hundreds of such clubs around the country, many of them launched and encouraged by ProShare.
Among the most successful is the Maydown Mergers club based in Londonderry, which has 19 members, all working in the local textile industry.
"It started more or less accidentally," said Mike Carroll, the founder. "I read an article about it and we got talking at work. The next thing, word got round and people were queueing up to join."
At launch, each of the 19 members contributed pounds 200 as a lump sum, plus pounds 25 a month, which has just gone up to pounds 30. In the first year, says Mr Carroll, the return was 15 per cent - but in the last three months this has topped 25 per cent.
"We use Infotrade to decide on investments," says Mike Carroll. "At first we did it manually, but there's so much more information you can get on- line."
Cybertrader 0181-904 2010 (software free, monthly subscription for on-line service, typically pounds 10-20 depending on usage and services).
Infotrade 0800 226600 (software free, basic subscription pounds 2.95 a month includes 2 hours on-line. Extra time at pounds 1.55/hr, with additional charges for specific services such as real-time prices and mortgage quotations.
ProShare 0171-600 0984, for information on investment clubs.