Hi Tom,
Many thanks for your interesting comments on this thread.

The one that interests me most is your latest, saying that the PRS "fee for a planned free-entry session is £7.62" and your very helpful link to the PRS tariffs.
Our pub has a planned free-entry session every 2 weeks (26 per year)
which means a modest and acceptable fee of £198.12 should apply.

Yet they demanded over £700 on the "basis of the square footage of the property" (i.e. the bigger the pub the more money) I am not privvy to the exact calculation, but it is totally at odds with the PRS website which does not mention square footage and we are certainly nevr more than 50 persons (let alone 100).

I will try taking this up with the PRS directly.

Thanks again everyone.
Jon