From Longman Dictionary of Contemporary Englishpresume on/upon somebody’s friendship/generosity etcpresume on/upon somebody’s friendship/generosity etcto unfairly ask someone for more than you should, because they are your friend, are generous etc It would be presuming on his generosity to ask him for money. → presume
Examples from the Corpus
presume on/upon somebody’s friendship/generosity etc• I will not presume upon your friendship any further. 