Article 1431

A debtor owing several monetary obligations to the same creditor may specify at the time of payment the obligation to which he intends the payment to be: applied. However, the payment is imputed first to any expenses, then to interest due and finally the principal.

If the debtor makes no such specification, the creditor may, within a reasonable time after payment, declare to the debtor the obligation to which he imputes the payment, provided that the obligation is due and undisputed.

In the absence of imputation under sub-Articles (1) or (2), payment is imputed to that obligation which satisfies one of the following criteria and in the order indicated:

an obligation which is due or which is the first to fall due;

the obligation for which the creditor has least security;

the obligation which is the most burdensome for the debtor;

the obligation which has arisen first.