An account is said to be "in arrears" if one or more payments have been missed in transactions where regular payments are contractually required, such as mortgage or rent payments, utility, or telephone bills. The term is usually used in relation to periodically recurring payments, such as rent, bills, royalties (or other contractual payments), and child support. Payment in arrears is a term describing payments made after a service has been provided. In this case, the use of the word "arrears" does not imply any breach.
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Arrears Calculation