*He's being **delinquent** on his debts*

> delinquent

> : failing to pay an amount of money that is owed

> [M-W](http://www.merriam-webster.com/dictionary/delinquent)

> ... *you will learn that once a person in our society has developed a history of being delinquent on his debts he will, most likely, continue those payment habits for the rest of his adult life.*

> [Cash Or Credit?: A Nuts and Bolts Guide to Effective Credit Management](https://books.google.fr/books?id=6NMtLN7G6sEC&pg=PA72&lpg=PA72&dq=%22being+delinquent+on+his+debts%22&source=bl&ots=tqWKbuAbtv&sig=k4YXfDcuvRey1nS-gF6jsXt8tlM&hl=fr&sa=X&ved=0ahUKEwj1xtip2ojMAhWDBBoKHbiqDSAQ6AEIGjAA#v=onepage&q=%22being%20delinquent%20on%20his%20debts%22&f=false)