in_arrears
1. [ adjective ] (accounting) late or behind in fulfilling obligations
Examples:

"an account in arrears"

Related terms: late
2. [ adverb ] in debt
Synonyms: behindhand behind
Examples:

"he fell behind with his mortgage payments" "a month behind in the rent" "a company that has been run behindhand for years" "in arrears with their utility bills"