LONDON -- If you want to be eligible for a dividend payment, or if you're watching for possible share-price falls, keeping up with ex-dividend dates can prove beneficial. So long as you hold the shares up to and including that day, you'll get your dividend money.

We have a number of companies from the FTSE 100 reaching their crucial dates next week. Here are three that will go ex-dividend next Wednesday, June 19.

Severn Trent (LSE:SVT)
Severn Trent declared a final dividend of 45.51 pence per share in May to provide a full-year dividend of 75.85 pence per share -- a rise of 8.2% on the previous year. That provides a yield of 4.3% on a share price of 1,760 pence. At the same time, the water company said its full-year dividend would be lifted by a further 6% to 80.4 pence per share, in line with the group's policy of maintaining growth equal to Retail Price Index plus 3%.

The dividend was a point of contention regarding the recently rejected bid for Severn Trent from LongRiver Partners, with the water supplier's board reckoning the £22 per-share bid did not take the payment properly into account.

United Utilities (LSE:UU)
United Utilities will go ex-dividend on the same day with respect to its final dividend of 22.88 pence per share. That adds to an interim payment to give a full-year total of 34.32 pence per share, and a yield of 4.7% on the current share price of 731 pence.

Along with other utilities companies, United Utilities has seen its share price pushed up of late as income-seekers move into the sector in search of dependable high yields, with the shares having risen to a P/E multiple of more than 17 based on forecasts for March 2014. However, if the yield can stay around 5%, that P/E rating could be fair value.

Land Securities (LSE:LAND)
Our third for next week is Land Securities, the real-estate investment trust whose shares have risen to 903 pence this year. Again we're looking at a final dividend, of 7.6 pence per share this time, for a full-year payout of 29.8 pence per share -- a rise of 2.8%, for a yield of 3.3%.

The firm's current valuation appears to reflect optimism for the future of the real-estate market, with forecasts for the year to March 2014 putting the shares on a P/E of nearly 24 -- and the dividend is set to rise over the next two years, too.

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