[5] Collison entered the 40th Young Scientist and Technology Exhibition with his project on artificial intelligence (nicknamed 'Isaac' after Isaac Newton, whom Patrick admired), finishing as individual runner-up.

[4][1] In 2007, he set up software company 'Shuppa' (a play on the Irish word siopa, meaning 'shop') in Limerick with his brother John Collison.

[14] In 2018, Stripe, under the direction of the Collison brothers, contributed $1 million to California YIMBY, a pro-housing development lobbying organisation.

[17] Both Collison and his younger brother John were featured on a young Irish persons rich list aired on an RTÉ television show during the 2008 Christmas period.

[18] On 18 July 2009, at the age of 20 and following the publication of the McCarthy Report, Collison outlined his ideas for the future of Ireland on popular talk-show Saturday Night with Miriam.

According to Collison, he reads books and is interested in a broad range of subjects on history, technology, engineering, fiction, philosophy, and art.

[21] Patrick O'Donovan called on the magazine and author to apologise to the people of Limerick "for the insult and hurt caused" by it.

[21] He also tweeted "I am calling on them to come to Limerick where I will gladly set the record straight in respect of what our county and city has to offer as opposed to what your work of fiction depicts," and "Please let me know when suits to visit.

[21] In April 2022, Collison married Swiss-American biochemist and Stanford University professor Silvana Konermann, with whom he co-founded the Arc Institute.