How are my transactions categorized? December 13, 2018 22:53 Updated We use an internal algorithm that automatically categorizes each transaction. You are also able to manually change the category for individual transactions. Comments 0 comments Please sign in to leave a comment. Related articles How can I change a transaction's category? Can I add another transaction category? Why are some numbers in my transactions green? My bank account category is wrong! I'd like to remove all my information from NerdWallet, per the GDPR.