Short answer. One year, if the parties never fixed a duration. Article 1629 gives a good-faith assignor's guarantee of solvency a default one-year term: one year from the assignment if the credit was already due, or one year after maturity if it was not yet due when the credit was sold to you.
What the law says
In case the assignor in good faith should have made himself responsible for the solvency of the debtor, and the contracting parties should not have agreed upon the duration of the liability, it shall last for one year only, from the time of the assignment if the period had already expired.
Civil Code, Article 1629 — Duration of Warranty of Solvency. Read the full provision →
What the law says
If the credit should be payable within a term or period which has not yet expired, the liability shall cease one year after the maturity.
Civil Code, Article 1629 — Duration of Warranty of Solvency. Read the full provision →
The default term is one year
Article 1629 fills a gap that comes up whenever a seller of a credit, called the assignor, agrees to answer for the debtor's solvency but the parties never spelled out for how long. It provides that in case the assignor in good faith should have made himself responsible for the solvency of the debtor, and the contracting parties should not have agreed upon the duration of the liability, it shall last for one year only, from the time of the assignment if the period had already expired. If the debt was already due when you bought the credit, the one-year clock starts running from the day you and the assignor completed the sale.
A different starting point for credits not yet due
The article treats a credit that was not yet payable at the time of the sale differently. It states that if the credit should be payable within a term or period which has not yet expired, the liability shall cease one year after the maturity. Here, the one-year period does not start from the sale itself but from when the debt actually becomes due. So if you bought a credit that matures later, the assignor's guarantee of solvency runs for a year measured from that later maturity date, not from the date of the assignment.
This only applies without an agreed duration
This one-year default only fills the gap the parties left open. If you and the assignor actually agreed on how long the guarantee of solvency would run, whether shorter or longer than a year, that agreement controls instead of the rule in Article 1629. The article exists precisely for the situation where the parties addressed the assignor's responsibility for solvency but said nothing about its duration, leaving the law to supply a reasonable, fixed cutoff rather than an indefinite one.
What this means for you as the buyer of a credit
If you bought a credit and the seller guaranteed the debtor's solvency in good faith without stating a time limit, you generally need to pursue any claim based on that guarantee within the applicable one-year period, counted from the assignment or from maturity depending on your situation. Waiting past that window risks losing the benefit of the guarantee entirely, even if the debtor genuinely turns out to be insolvent.