London mathematical society http://www.lms.ac.uk/membership/membership-categories

American Mathematical Society http://www.ams.org/membership/individual/individual

Royal Statistical Society http://www.rss.org.uk/RSS/Join_the_RSS/RSS/Join_the_RSS/Join_the_RSS.aspx?hkey=7dd5d66d-f5c3-428f-88df-627454781046&hkey=4a913889-e76d-49ca-9ece-0ca731bcebee

British Computer society (which is a chartered institute and membership it in gives more benefits) http://www.bcs.org/category/5780

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