LONDON -- With so many companies boosting their dividends in line with improving full-year results, investors will surely want to know when they'll be eligible for payment -- whether they want to buy in time to get it or are looking for a bargain share price on ex-dividend day.

Here are three FTSE 100 companies going ex-dividend in the week commencing March 18.

Aviva (LSE:AV) (NYSE:AV)
Aviva, the insurer that famously slashed its final dividend by 44% last week, will go ex-dividend next Wednesday, March 20. For those who also received the firm's interim dividend, the full-year cash payout will amount to 19 pence per share, which is 27% less than the previous year. But even after the fall, it represents a yield of 5.9% on the current share price of 324 pence, and that's still one of the best in the FTSE 100.

We have, of course, no forecasts for Aviva's 2013 dividend yet, as existing ones were all based on pre-cut levels. But with the shares on a forward price-to-earnings ratio of less than eight, a lot of people will be seeing them as a bargain now.

HSBC Holdings (LSE:HSBA)
Also on next Wednesday, HSBC Holdings shares will go ex-dividend. The international bank announced a 10% rise in its full-year dividend to $0.45 per share on March 4, representing a yield of about 4% on the current share price of 734 pence.

HSBC also told us it plans to lift its first three dividend payments for 2013 by 11%. If that is reflected in the fourth quarter, too (and we will surely be hoping for a bit more than that for the final dividend), we should be looking at a yield of about 4.5% by December 2013.

InterContinental Hotels (LSE:IHG)
Wednesday is also ex-dividend day for InterContinental Hotels Group, which on Feb. 19 reported a 10% rise in operating profit for the year to December 2012. Adjusted earnings per share rose by 8.5% to $1.42, enabling the firm to lift its full-year dividend by 16% to $0.64 per share.

With the shares currently trading at 2,019 pence, that's a yield of only a little more than 2%, but it's the third year in a row of dividend growth, with further rises of about 8% and 11% forecast for 2013 and 2014, respectively.

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Alan does not own any shares mentioned in this article. The Motley Fool has a disclosure policy. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. Try any of our Foolish newsletter services free for 30 days.