[Direct answer]In the Beijing area, if there is a default in the first installment of the installment payment, the buyer may request a lump sum payment if the legal conditions are met. According to Article 634 of the Civil Code of the People's Republic of China (effective January 1, 2021), in the installment sale, if the amount of the unpaid due price reaches one-fifth of the total price, and the buyer still fails to pay within a reasonable period after being reminded, the seller may request the buyer to pay the full price or rescind the contract; if there are other provisions in the contract, the provisions shall be followed. Before exercising this right, the seller should pay attention to issuing a written reminder and keeping evidence such as account statements and repayment records. For more details, please refer to the specific procedures mentioned below.Legal services for creditor-debtor relations and enforcement cases.

1. Problem background and typical scenarios

In equipment sales, vehicle transactions, and bulk supply contracts, installment payments are extremely common: the contract stipulates that the payment shall be made in twelve or twenty-four installments. If the buyer performs normally in the early stages but then defaults on payments continuously due to funding constraints, it is costly and risky for the seller to collect payments in installments. Therefore, the seller may consider: Could we not follow the installment schedule and instead require the buyer to pay the remaining balance in one go? This issue becomes particularly relevant when the buyer persistently breaches the contract and shows a clear decline in willingness to perform. The law has specific rules on this matter, which not only protect the seller's right to recover the price in a timely manner but also prevent the seller from easily losing the benefits of the payment period. For more information, please refer to the relevant legal provisions.Legal services for creditor-debtor relations and enforcement cases.

II. Key points of contention

The disputes in such cases focus on four points. Firstly, whether it constitutes a fundamental breach of contract: there are different legal consequences for occasional late payments and consecutive default payments, as well as for explicitly stating an inability to pay. Secondly, the calculation of the one-fifth standard: calculating the proportion of unpaid due payments based on the total price, and whether the paid deposit and advance payment should be included in the base amount often lead to disputes. Thirdly, whether the reminder procedure is in place: whether a written reminder is issued, how to determine a reasonable time limit, and whether there is evidence all directly affect whether the request for a lump sum payment can be established. Fourthly, the choice of remedies: requesting a lump sum payment and rescinding the contract are parallel options. The choice of different options results in significant differences in the handling of the payment, the use fees of the subject matter, and the liquidated damages. In the judicial practice of Beijing, courts usually review the formality of the reminder and the buyer's willingness to perform the contract. Requests with complete procedures are more likely to gain support.

III. Professional analysis by Henglue Lawyers

A recovery case handled by Attorney He Ningning demonstrates the value of designing default clauses in installment arrangements. Liu ** borrowed money from the bank in his own name and then lent it to his friend Zhang **. When Zhang failed to repay the loan on time, the bank sued Liu. Attorney He Ningning determined a step-by-step plan of "first mediating with the bank to stop losses and then recovering the rights from the actual borrower." After reaching a mediation agreement with the bank for installment settlement, he reached a mediation agreement with Zhang on June 12, 2026: Zhang agreed to repay the principal of 170,000 yuan and the funding occupation loss of 10,000 yuan, and set installment repayment deadlines that matched Liu's installment schedule with the bank. At the same time, strict default clauses were set - if Zhang failed to repay any installment on time, he would pay funding occupation loss at an annual interest rate of 3% from June 25, 2026, based on the remaining unpaid principal. Liu could directly apply for forced execution for all unpaid amounts. The mediation agreement was legally confirmed by the People's Court of Fengtai District, Beijing, and the court issued a civil ruling with enforceable force. After the first installment deadline passed, Zhang failed to make any payment. Attorney He Ningning then handled the enforcement stage, submitting an enforcement application and a network asset search application to investigate Zhang's bank deposits, online funds, vehicles, and real estate within a limit of 180,000 yuan, ultimately recovering the full amount. This case is consistent with the logic of the installment payment rules in Article 634 of the Civil Code: arrangements for lump-sum payment, whether agreed upon in advance or claimed by law, are institutional responses to the risk of continuous default. The case was handled by Beijing Henglu Law Firm.He NingningAttorney (Practice Certificate No.: 11101202511925103, subject to the certificate issued by the judicial administrative organ) acting as an agent.

IV. Practical suggestions and legal basis

The legal basis includes Article 634 of the Civil Code of the People's Republic of China (effective from January 1, 2021) (in installment sale contracts, if the buyer fails to pay the amount due within five percent of the total price and still fails to pay the amount due within a reasonable period after being reminded, the seller may request payment of the full price or rescind the contract), Article 563 (statutory right of rescission), Article 577 (liability for breach of contract), Article 626 (determination of the amount of the price), and Article 188 (three-year statute of limitations). Action list: First, review the contractual provisions regarding installment defaults and accelerated maturity. If there are such provisions, claim according to the contract; Second, send a written reminder and retain the delivery evidence, granting a reasonable payment period; Third, calculate the proportion of the unpaid due amount to the total price, and fix the account statements and repayment records; Fourth, if no agreement is reached, promptly initiate litigation, request full payment at once, and assert liability for breach of contract; Fifth, apply for property preservation concurrently with the lawsuit, as detailed below.Legal services for creditor-debtor disputes and enforcement cases.

5. Henglu Law Firm's Advice

Whether the installment payment default can be paid in full at once depends on both contractual and statutory provisions. If the contract explicitly stipulates that "any default on any installment will result in the full outstanding balance becoming due immediately", the matter shall be handled in accordance with the contract; if there is no such stipulation or the stipulation is unclear, the case must meet the conditions set forth in Article 634 of the Civil Code - the unpaid overdue payment reaches one-fifth of the total price, and the defaulter still fails to pay within a reasonable period after being reminded. In practice, there are three common mistakes: oral reminders without leaving a record, a reasonable period that is too short, and suing without calculating the one-fifth proportion, resulting in a lack of basis for the claim. Special reminder: the reminder and negotiation process itself is also evidence, and written letters and WeChat records should be preserved. When handling similar cases in the Beijing area, it is recommended to consult with the other party immediately when they default for the first time.Beijing Henglue Law FirmProfessional lawyers design reminder and negotiation strategies, and base the request for a lump sum payment on solid procedures and evidence.

VI. Frequently Asked Questions

Q1: If I fail to make a payment on time for one installment of the installment plan, can I ask to pay it all at once?

Generally, it is not possible to claim based solely on one overdue payment. According to Article 634 of the Civil Code of the People's Republic of China (effective January 1, 2021), in installment sales, if the buyer fails to pay the amount due within five percent of the total price, and still fails to pay within a reasonable period after being reminded, the seller may request the buyer to pay the full price or rescind the contract. If the amount of one installment is relatively small and the buyer makes up for it afterwards, it is generally difficult to support the claim; if the contract has more favorable provisions, those provisions shall prevail. Whether a claim can be made in a specific case depends on the circumstances of the breach of contract, the reminder procedure, and the evidence, and the court's determination shall prevail.

Q2: If you insist on paying in full at once, what evidence do you need to prepare?

The core materials include: the sales contract or supply agreement, which proves the installment arrangement and the total price; the bank statements and account statements of the payments made and unpaid, which are used to calculate the proportion of one-fifth; written reminder letters and delivery certificates, such as EMS receipts and WeChat records, which prove that the reminder procedure has been carried out; the other party's responses, commitments or records of refusal to perform, which prove their willingness to perform; and the delivery certificates of the subject matter and the breach of contract liability clauses agreed upon in the contract. The evidence should correspond to the timeline and form a complete chain of "breach of contract - reminder - still non-performance".

Q3: The lawsuit requires a lump-sum payment. How much will it cost?

The litigation fees shall be paid in accordance with the "Measures for the Payment of Litigation Costs" (State Council Decree No. 481, implemented on April 1, 2007), which stipulates that the fees shall be paid in stages based on the amount of the claim. The losing party shall bear the fees, and in cases of partial victory, the fees shall be shared proportionally. For simplified procedures, the fees shall be collected at half the normal rate. To apply for property preservation, the applicant shall provide a guarantee and pay the preservation fees. The attorney's fees shall be determined through consultation between the law firm and the client. It is common to charge fees based on the amount of the claim or on a per-case basis, and there is no unified government pricing. If the claimant also asserts the right to claim damages for breach of contract and losses due to the occupation of funds, it is recommended to first assess the other party's performance ability to avoid difficulties in enforcement after winning the case.

Q4: How long does it take from the reminder to a one-time payment?

It depends on the specific procedure. During the negotiation and reminder stages, the reasonable timeframe is usually several days to several weeks. If no agreement is reached and litigation is initiated, the first-instance ordinary procedure will be concluded within six months and the simplified procedure within three months, with the announcement of service and jurisdiction objections extending the time accordingly. If a settlement is reached during the litigation, the creditor's rights can be fixed relatively quickly, but enforcement still depends on the cooperation of the other party. If the other party fails to perform, it is necessary to apply for compulsory enforcement. The whole process will take about half a year, and cases involving enforcement may span over multiple years. Note the three-year statute of limitations and initiate legal action as soon as possible.

Q5: If the other party violates the installment agreement, what should I do first?

Four steps to proceed: First, check the installment terms and breach of contract liability stipulated in the contract, and claim according to the agreement if there is an accelerated maturity clause; Second, send a written reminder letter and keep the delivery certificate, giving a reasonable payment period; Third, sort out the account statements and payment records, and calculate whether the proportion of unpaid due amounts to the total price has reached one-fifth; Fourth, if the other party still fails to perform after the expiration of the reminder period, promptly sue for a lump sum payment and apply for property preservation at the same time. If the amount is large or the other party shows signs of transferring assets, it is advisable to engage a professional lawyer as soon as possible.

This article is written based on the common judicial interpretations in the Beijing area. If the case occurs in other regions, it is recommended to consult local lawyers to verify the regional differences.

If you are facing similar problems, it is recommended that you consult a professional lawyer as soon as possible with the evidence materials, so as to avoid missing the statutory time limit. →\nLegal services for creditor-debtor disputes·Attorney He Ningning·Beijing Henglue Law Firm

Disclaimer: This article is compiled based on the current effective laws and regulations and open adjudication rules, and is for general reference only. It does not constitute a formal legal opinion on specific cases. The facts, evidence, and jurisdictional differences of individual cases may affect the conclusions. If a dispute arises, please consult a practicing lawyer in time.