The following is rough guidance on how many poker chips you may need for your own poker evenings, followed by general advice on splits. You also need to take into account the variation of poker you will be playing and the betting tendencies of your mates (are they aggressive bettors or Yorkshiremen with scorpions in their pockets?):

Most people go for a 3:2:1 split on anything up to 400 chips. That is to say a 300 chip set would contain 150 of one colour (lowest denomination), 100 of a second colour and just 50 of the third colour (highest denomination). For example:
150 Red (3)
100 Blue or Green (2)
50 Black (1)

Please see which denominations usually go with which colours.

Once you increase the number of chips over 400, you could add in a fourth or fifth colour. Any more than five colours and you may find it difficult to keep track of bets unless the chips are printed with a denomination. Generally, you want to keep 60% to 70% of your chips in the lower and middle denominations. A typical choice would be:
150 White
150 Red
50 Green
50 Black

For 500 chips, this is the set we use for Gamble.co.uk staff games:
150 White
150 Red
100 Blue
50 Green
50 Black

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