There is no legal effective date for IOUs, only the legal litigation date for IOUs. If there is no repayment date, the IOU will not become invalid after it expires.

If there is no agreed repayment period, the limitation of action shall be calculated from the day after the lender claims to return it.

IOU for the agreed repayment period: the limitation of action shall be calculated from the day after the repayment period expires.

If there is no agreed repayment period, the creditor can claim the right within 20 years, but the time limit for claiming the right again is two years from the date when the first claim fails to be realized. Otherwise, the extended unprotected lender can ask the borrower to write a repayment plan or a reminder certificate before the expiration of the limitation period, so that the limitation of action can be recalculated from the date when a new agreement is concluded.

Extended data:

Legal basis:

According to the Contract Law of People's Republic of China (PRC):

Article 61? After the contract comes into effect, the parties have not agreed or clearly agreed on the quality, price or remuneration, place of performance, etc. They can supplement the agreement; If a supplementary agreement cannot be reached, it shall be determined in accordance with the relevant provisions of the contract or trading habits. ?

Article 62 Where the parties have not clearly agreed on the contents of the contract and cannot be determined according to the provisions of Article 61 of this Law, the following provisions shall apply:

(a) the quality requirements are not clear, in accordance with national standards and industry standards; If there is no national standard or industry standard, it shall be implemented according to the usual standard or the specific standard that meets the purpose of the contract.

(2) If the price or remuneration is not clear, it shall be performed according to the market price at the place of performance when the contract is concluded; If government pricing or government-guided pricing should be implemented according to law, it shall be implemented in accordance with the provisions.

(3) Where the place of performance is unclear, if money is paid, it shall be performed at the place where the party receiving the money is located; Where real estate is delivered, it shall be performed at the place where the real estate is located; Other targets shall be performed at the place where the party performing the obligations is located.

(4) If the time limit for performance is not clear, the debtor may perform at any time, and the creditor may also request performance at any time, but the other party shall be given the necessary preparation time.

(5) If the method of performance is not clear, it shall be performed in a way conducive to the realization of the purpose of the contract.

(six) if the burden of performance expenses is not clear, it shall be borne by the party performing the obligation.

Article 206 The borrower shall repay the loan within the agreed time limit. If the term of the loan is not agreed or clearly agreed, and cannot be determined according to the provisions of Article 61 of this Law, the borrower may return it at any time; The lender may urge the borrower to return it within a reasonable period of time.

China laws and regulations database: People's Republic of China (PRC) contract law.