LONDON -- Whether you want to buy in time to be eligible for a company's dividend payment or you're looking to buy on a share price drop when the time has passed, it pays to know when your target companies are due to go ex-dividend.

Here are three FTSE 100 companies going ex-dividend in the week commencing March 25.

British Sky Broadcasting (LSE:SKY)
Wednesday will be ex-dividend date for British Sky Broadcasting Group, with an interim dividend of 11 pence per share payable on April 23. The payout, announced with halftime results on Jan. 31, represents a 20% rise on the previous year.

The firm's dividend payouts have been rising steadily for the past five years, with analysts forecasting a further 19% rise for the full year to June 2013. The expected level of about 28 pence per share represents a yield of 3.1% on the current share price of 894 pence.

Prudential (LSE:PRU) (NYSE:PRU)
With some insurers slashing their dividends of late, Prudential shareholders were reassured with a 15.9% rise in the firm's annual payout for 2012 to 29.19 pence per share, announced with full-year results on March 13. On the closing price the previous day of 1,029 pence, that represented a yield of 2.8%, although the shares have spiked since then before settling back to today's level of 1,114 pence.

Prudential's dividend yields are lower than some of its competitors', but the annual payout has been pretty dependable, and further growth is forecast for the next two years. The ex-dividend date for the final payment of 20.79 pence is March 27.

Schroders (LSE:SDR)
Again on Wednesday, Schroders will go ex-dividend with respect to its final payment of 30 pence. The total dividend for the year ending December 2012 amounts to 43 pence per share for a yield of 2.1% at the time of the announcement on April 7 -- the shares have subsequently risen from 2,036 pence to 2,147 pence.

Although Schroders' earnings per share have been erratic over the past few years, the investment manager has kept its well-covered dividends steady and rising, with more of the same forecast for this year and next.

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Alan Oscroft has no position in any stocks mentioned. The Motley Fool has no position in any of the stocks mentioned. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.