Penalty calculator for taxes and insurance premiums. Calculation of penalties: universal online calculator Example of calculating interest at the refinancing rate


Purpose of the application:

Preparation of a full calculation of interest under Art. 395, 317.1 of the Civil Code of the Russian Federation and calculation of penalties, which can be used as an appendix to the statement of claim;

Operational verification of settlements during a court hearing.

The rates of the Central Bank of the Russian Federation for settlements under Articles 395 and 317.1 of the Civil Code of the Russian Federation are updated on the day of their publication. The next change in legislation on changing the calculation algorithm from August 1, 2016 has been taken into account by the developers.

The updated version of the mobile application (August 2016) has expanded capabilities. This version, in particular, provides:

Possibility of reducing (interim payments) or increasing the amount of debt (performing a new amount of work, etc.) during the settlement period;

The new procedure for determining the number of days in a year in relation to Art. 395 of the Civil Code of the Russian Federation after 03/23/16.

In addition, application owners will have access to a private section of the site with similar advanced calculator capabilities.

Considering that our lawyers also use the calculator, we are constantly working to improve the functionality and timely update the latest data for the calculator to work correctly.

You can download the application using the following links:

For the convenience of people interested in charging a penalty to a debtor, we have developed a calculator for calculating it. Now, in order to correctly calculate the amount of the penalty for delay in the debtor’s obligation, you will only need to enter the amount of the debt, the period of delay and the amount of the penalty. By using the calculator on the website of the Lex Group of Law Companies, you can be sure that the penalty is calculated correctly according to the data you entered.
The possibility of collecting a penalty for delay in fulfilling an obligation is provided for in Art. 330 of the Civil Code of the Russian Federation, according to which a penalty (fine, penalty) is a sum of money determined by law or contract, which the debtor is obliged to pay to the creditor in the event of non-fulfillment or improper fulfillment of an obligation, in particular in the case of delay in fulfillment.


When collecting a penalty, the creditor should keep in mind that the agreement on the penalty must be made in writing, regardless of the form of the main obligation. Failure to comply with the written form shall result in the invalidity of the liquidated damages agreement.
It is worth noting that in judicial practice in cases of collection of penalties, the greatest disputes arise in terms of determining the moment when the debtor’s delay occurred.
The subject of proof for a claim for a penalty will be: the existence of an obligation of the debtor, non-fulfillment or improper performance thereof and the existence of liability for such a violation in the form of a penalty.


However, even if the creditor proves all the above circumstances, the court may refuse to collect a penalty in the declared amount, since in civil law there is a mechanism for reducing the penalty provided for in Art. 333 Civil Code of the Russian Federation.
By virtue of this article, if the penalty payable is clearly disproportionate to the consequences of the violation of the obligation, the court has the right to reduce the penalty. A reduction of the penalty determined by the contract and payable by the person carrying out business activities is allowed in exceptional cases if it is proven that the collection of the penalty in the amount stipulated by the contract may lead to the creditor receiving an unjustified benefit.
It should be noted that there are no clear criteria for determining the proportionality of a penalty, which gives rise to discrepancies in judicial practice.
Thus, the mechanism for collecting a penalty in the desired amount, as well as reducing it to the desired amount, is quite complex and requires the parties to perform actions to prove the above circumstances.

Penalty interest agreed upon by the parties at the conclusion of the contract or established by law, which the debtor is obliged to pay in case of delay in payment, is called a penalty. To correctly calculate the penalty when filing a claim in court, sending a claim to the counterparty and further correctly reflecting the transaction in accounting documents, there is a special procedure for calculating and accounting for late payment penalties.

Contractual penalty

This means that the penalty (P) is agreed upon in advance by the parties to the business and is documented. It can be in the form of a certain amount or calculated as interest for each day of delay.

Formula for calculating penalties (P):

P = amount of debt * size P * number of days overdue / 100

Let's look at an example:

The company had to pay a debt of 5,000 rubles on January 31, 2017. The actual payment occurred on February 20, 2017. in the amount of 3,000 rubles, and 02/25/2017. another 2000 rubles were paid. At the end of the month, the creditor sends a calculation of the claim to the debtor, based on the size of P equal to 0.1%.

The debtor company will pay the creditor, in addition to the main current debt, the following amount of P:

  1. 5000*0.1*20 days/100 = 100 rubles;
  2. 2000*0.1*5 days/100= 10 rubles;
  3. Total 110 rubles.

Legal penalty

If the contract does not stipulate liability for failure to fulfill monetary obligations, if late payment occurs, the concept of legal P () comes into force.

Note: according to this, the debtor, in case of delay, must pay either the contractual amount of the penalty or the legal amount, unless otherwise specified in the agreement of the parties.

Legal P is calculated at the refinancing rate of the Central Bank of Russia. The introduction of this rate is possible in the following cases:

  • Calculation of fines and penalties for tax obligations (part of the rate for each day of non-payment);
  • Payment by P for late payment of a loan or interest;
  • When taxing a deposit in rubles with personal income tax, in the case where the interest rate is greater than the refinancing rate;
  • Payment of compensation for delayed wages (more than a share of the refinancing rate approved on September 19, 2016 in the amount of 10%).

Rule for calculating penalties at the refinancing rate:

P = amount of debt * refinancing rate * Days of delay/100 * part of the refinancing rate.

It should be noted that when calculating P, the counting of days begins from the next day after the start of the delay, and ends with the day appointed for payment of the penalty.

If the rate changes during the payment calculation period, P is calculated separately for each of its values.

If it is difficult to calculate penalties or to save time, you can take advantage of the opportunity to calculate it using an online calculator.

Late payment of tax

The procedure for accrual and calculation of taxes is regulated by

When will the State Tax Administration accrue to the organization P:

  • If the amount of tax transferred to the budget is underestimated;
  • In case of late payment, taxes will be assessed.

Let's consider a general example of accrual in the case when the refinancing rate changed during the period of non-payment.

Input data:

  • Amount not paid on time – 5000 rubles;
  • The payment delay period was 30 days, of which 18 days – the refinancing rate was at 10.5%, and 12 days – 10%.

Example of calculating late payment penalties:

P = (5000 rubles x 10.5 percent/100/300 x 18 days)+(5000 rubles x 10 percent/100/300 x 12 days) = 31.5+20=51.5 rubles.

When determining the number of days of violation of payment terms, the enterprise needs to clarify the requirements of the local State Tax Inspectorate regarding the inclusion of the last day in the general period of payment delay, since only the first day of this period is precisely specified in the NKRF.

Late advances

Depending on the type of taxes, the procedure for calculating and paying taxes differs. Let’s consider only the specifics; otherwise, the procedure for calculating and paying is general:

  • Unpaid advances on income tax - interest is accrued after 1 month from the beginning of the violation of the deadline;
  • Unpaid advances on land tax - in addition to the standard accrual of P, legal entities and citizens of the Russian Federation are subject to penalties in the form of 20% of the debt. If the delay in payment was intentional, the fine is 40%;
  • Unpaid advances on property tax - P is assessed by local State Tax Administrations. If the owner of property subject to taxation has not received a notice of tax payment and payment at the beginning of the reporting period, he must contact the local State Tax Administration;
  • Unpaid advances for transport tax - payment is made once a year to the local State Tax Administration, P is accrued after 3 months from the date of the violation. If the non-payment is intentional, an additional 30% penalty on the tax debt will be charged.

Enterprise accounting

In accounting, penalties are taken into account in expense accounts (to the budget), which are not subject to taxes.

The size of P does not affect changes in the tax base, so the temporary difference between tax and accounting accounting is not detected.

Legal subtleties

Penalties (Articles No. 72 and No. 75 of the NKRF) are not a measure of tax liability, but are intended to compensate for budget losses.

Late payment penalties cannot be suspended by applying for an investment tax credit.

For late payment, P is not charged in the following cases:

  • From the date of seizure of the property of an individual (who is not an individual entrepreneur) until the day the proceeds are deposited into the state budget;
  • When the State Tax Administration seizes the accounts, funds, and property of the taxpayer;
  • If the arrears occurred after compliance with legal requirements regarding the payment procedure, and there is an official document confirming this;
  • If the payer has surpluses remaining from the payment of previous amounts, fines and penalties, on the date of the required payment;
  • If the payer’s existing tax surplus in the State Tax Tax Administration partially covers P, then the accrual occurs in an amount that is not covered by the overpayment.

Surplus payments accrued to the taxpayer can only be used in the following cases:

  • To repay P accrued by the tax administration;
  • To pay city, state and federal tax obligations.

The State Tax Administration has the right to forcibly collect P from the defaulter by seizing the amount of the debt on funds in banks or on his other property.

Every business, large or small, must avoid the occurrence of late payments. These bills are not going anywhere, and you will still have to pay them. But the amount will be greater, because for failure to pay on time, a penalty (penalty) will be charged. Let's consider options for finding the amount of penalties based on the refinancing rate.

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What are penalties and forfeits?

According to the Civil Code, “fine” and “penalty” have no fundamental differences. Used mainly as synonyms. But the following definition is accepted.

Penalties are penalties imposed on a company for breach of contract or failure to fulfill obligations before the law. The amount of the fine is fixed, most often it is a percentage of the total amount. For example, in the contract the terms of penalties may be specified as follows: “In case of untimely delivery of consumables, the company will be subject to a fine of 120 thousand rubles.”

Penalty is a type of penalty. Responsible for late payments. Its size increases with every day of debt. Thus, a penalty for late payment is added daily to the amount of debt. Calculated as a percentage of the total amount of outstanding obligations. For example, “For late payment of fees for services, the debtor is obliged to pay a penalty in the amount of 1% of the full amount of the debt for each day of delay.”

Legislative acts regulating the calculation of penalties

The basis is Article 346, which states that the tax is established only by the Codes in force in the country. It states that the following courts have the right to resolve tax disputes:

  • Supreme.
  • Arbitration.
  • Constitutional.

Also acts that regulate the calculation are:

  1. Tax code.
  2. Civil Code.

Why is calculation necessary?

Let us assume that the payment obligations do not stipulate any penalties. Thus, in the event of a violation of financial obligations by one of the parties, it will be necessary to calculate a legal penalty. It is based on the refinancing rate.

Procedure for calculating penalties

  1. Determine whether the amount of the penalty is considered by the terms of the signed agreement. (If the amount is specified, then there is no need to perform subsequent actions).
  2. The penalty will be calculated based on the refinancing rate. It is necessary to find out the rate for the period of delay.
  3. Use the formula to calculate.

Calculation of interest at the refinancing rate

Every time you borrow money, you must remember that you will have to pay interest for using someone else’s money. The calculation of such interest is always based on the refinancing rate. Each bank (or other company issuing funds) independently sets the percentage of overpayment. It can be either equal to the refinancing rate or much higher than it. The second option is more often used, in which the bank’s risk and its profit are invested.

Interest on deposits is also calculated taking into account this rate. Knowing its size, you can easily calculate the deposit interest, which is subject to taxation. The tax is calculated at 35% of the interest on the deposit, the amount of which exceeds 13.25% (this limit is taken from the refinancing rate of 8.25% + 5%).

Calculation of penalties at the refinancing rate

As a penalty for violating the payment deadline, a penalty is charged. Its dimensions can be agreed upon when signing the contract. If initially both parties did not spell out this clause, then the relationship between them is governed by Article 395 of the Civil Code. Penalty is a percentage of the debt amount that is calculated daily. When the time comes to pay bills, you can calculate in advance the amount of penalties that have accumulated during the period of delay. And it begins to accrue the very next day after the end of the payment period.

If the rules for calculating penalties are not specified in the agreement, the interest is considered equal to the refinancing rate. It is established for the country's banks, which use money from the Central Bank when issuing loans. For the last few years, the rate has been equal to 8.25%. This value was established back in 2012.

Then to calculate the penalty you need to know:

  1. Payment amount.
  2. Late payment period (it is worth noting that in the financial calendar a month consists of 30 days, and a year consists of 360 days).
  3. Refinancing rate during the period of delay.

Formula for calculating penalties at the refinancing rate

To determine the amount of the penalty, use one of the formulas:

P = C x B x (P/100) / 300, Where:

In the formula, the rate is divided by 100. The Central Bank announces the value as a percentage, and to calculate it it must be converted into shares. Then the division by 300 is also explained by the condition set by the Central Bank that 1/300 of the refinancing rate is taken to calculate penalties.

P = C x B x (P/100) / 360, Where:

P is a penalty that is subject to accrual.

C is the amount of the initial payment that was not paid on time.

B is the time period (unit of measurement is day).

P is the current refinancing rate.

If the refinancing rate has changed during the delay, the calculation becomes a little more complicated. The entire period is divided into several parts (before and after the rate change) and calculations are carried out for these periods separately. Then the amount of penalties received is the final penalty at the refinancing rate.

Example of penalty calculation

Let's look at a simple example. Let's assume that the company has not paid a bill in the amount of 150 thousand rubles, and the debt has already lasted 20 days. The refinancing rate has not changed since 2012. It is 8.25% (or 0.0825).

Substituting all this data into the calculation formula, we get the amount of penalties at the moment:

Penalty = 150,000 x 20 x (8.25/100) / 300 = 825 rubles.

Thus, the enterprise is no longer obliged to pay not 150 thousand rubles, but 825 rubles more. The percentage of debt depends on the initial amount, so after another 20 days the debt will be:

150000+825+825=151650 rubles.

Let's look at an example of a calculation where the rate has changed during the period of delay.

Let’s say that the company owes 150 thousand rubles, and the debt has already lasted 20 days. Of these, the first 10 days the rate was 8%, and the second 10 days – 8.25%. Then:

Penalty = 150,000 x 10 x (8/100) / 300 + 150,000 x 10 x (8.25/100) / 300 = 812.5 rubles.

It is possible to make such calculations easier by entrusting them to technology. Now there are online calculators on the Internet that will help you calculate the amount of the penalty. Simply enter the amount of debt and days overdue.

Calculation of tax penalties

If tax payments are not made within the prescribed period, the defaulter may be charged not only a penalty, but also other measures.

P = C x B x (P/100) / 300, Where:

P is a penalty that is subject to accrual.

C is the amount of the initial payment that was not paid on time.

B is the time period (unit of measurement is day).

P is the current refinancing rate.

In the formula, the rate is divided by 100. The Central Bank announces the value as a percentage, and to calculate the penalty they must be converted into shares. Then the division by 300 is also explained by the condition set by the Central Bank that 1/300 of the refinancing rate is taken to calculate penalties.

Calculation of penalties at the refinancing rate for an arbitration court

Such calculations can be made:

  1. According to the formula:

    P = C x B x (P/100) / 360, where:P is the penalty that is subject to accrual.

    C is the amount of the initial payment that was not paid on time.

    B is the time period (unit of measurement is day).

    P is the current refinancing rate.

    In this formula, 360 is the sum of days in a fiscal calendar year.

  2. Use the official website of the arbitration court. On its pages there is a calculator designed for such calculations.

The initial data required for the calculation are:

  • The amount of debt including VAT (the entire amount of unpaid funds including taxes).
  • Percentage of taxation (there is a tax of 18, 10 and 0% for tax evaders).
  • Date of the first day of delay.
  • Date of payment.
  • Refinancing rate (it is set by the Central Bank of the Russian Federation on its website).

Any citizen or organization entering into any material relationship must always remember that in case of failure to fulfill their duties or performance not as required by law, they may be subject to the burden of paying a penalty in its various types.

For example, payment of a penalty may be provided.

However, when presenting a requirement to a counterparty that he pay a penalty, you need to be able to calculate it correctly, and for this there is a special formula for calculating the penalty, which will be discussed in detail in this article.

Penalty can be understood in several senses.

In a broad sense, it generally refers to a punitive sanction against the violator of obligations.

This includes such varieties as fines, penalties and the penalty itself in the narrow sense of the word.

Subjects of most material relations can provide in their agreement one of these options as liability for bad faith.

In fact, the concepts of penalties and penalties have the same meaning. However, in practice, questions may arise about how to calculate them, so you still need to distinguish one concept from another.

Thus, a penalty in the narrow sense and a penalty are measures of liability in the form of a fine, which are provided for in the contract by its parties.

However, the penalty has a fixed amount for failure to fulfill some obligation, and the penalty is expressed as a percentage of a certain amount (for example, 0.5% of the cost of work or goods supplied) for each day of delay.

The penalty may be established by law, and then it does not matter whether it is mentioned in the contract (for example, under the law on the protection of consumer rights), and therefore compensation must be demanded in court.

Formula for calculating penalties

You need to know the formula for calculating penalties under a contract in any case.

If a citizen does not have the opportunity to seek help from a lawyer, he must know how to correctly calculate the penalty in order to make a claim for its payment to the violating party to the contract.

If the person himself is in violation of his obligations, knowledge of the calculation will also be useful to him so that he can check the correctness of the amount of the penalty put forward by the counterparty in the claim and avoid making an error in the form of an overpayment.

The standard formula for calculating the penalty, the amount of which is determined by the contract, is as follows:

Contract amount * Interest rate * Overdue period

  1. The contract amount is an indicator indicating the number from which the penalty will be calculated. It can be either the cost of the contract as a whole (for example, in a purchase and sale relationship, if the buyer has not paid the cost of the goods at all), or some part of the amount that the counterparty has not paid (for example, partial postpayment has not been made after delivery goods or service).
  2. The percentage rate is a numerical value (takes place in the contract) characterizing the very amount of liability for the overdue party.
  3. The period of delay is the period of time when one of the parties is late in fulfilling its obligation (the goods were not delivered or payment was not made). It is counted from the day following the last day for fulfilling the prescribed obligation.

Please note: the agreement may not provide for a specific percentage of penalties. In this case, the penalty is subject to calculation at the refinancing rate of the Central Bank of the Russian Federation.

Calculation of penalties at the refinancing rate

The formula for calculating the penalty at the bank rate is very simple, however, before proceeding with the calculation, it is necessary to check the current rate number, as it may periodically increase.

You can view this information on the Internet. Also, in addition to this, the calculation of penalties at the rate of the Central Bank of the Russian Federation has the following features.

  1. It should not be confused with the above formula for calculating penalties.
  2. As an indicator of the rate, you should use either the refinancing rate itself (when Article 395 of the Civil Code of the Russian Federation is applied, that is, for most cases of non-fulfillment of agreements, contracts, etc.), or 1/300 of the bank rate (used to calculate penalties for taxes and fees).
  3. In this calculation, you need to take the following indicators for the number of days: 360 to indicate the year and 30 to indicate the month.

As an example, we will consider the formula for calculating penalties under Article 395 of the Civil Code of the Russian Federation; it has the following form:

Penalty = (number of overdue days * contract amount * refinancing rate) / 360 days.

If the agreement provides for a different number of days to understand the year or month (for example, one year is 350 days), then when calculating, you must be guided by the indicator established by the agreement.

Features of calculating penalties

  • Penalty interest is subject to accrual until the counterparty fulfills the overdue obligation (despite the change in the rate during this time, the initially taken rate, or the rate under the contract, if any, will be applied to the entire period of delay).
  • You need to be able to distinguish between a penalty for failure to fulfill an obligation and interest for using someone else’s money. The last case occurs in monetary obligations, when, for example, the borrower did not repay the loan amount on time. Or it may refer to a loan agreement.
  • Despite the wealth of existing information on the Internet that helps to calculate the penalty and not confuse its specific type, in complex, special cases (for example, a large number of payments from the counterparty, some of which were repaid after the specified period, a significant amount of the contract, etc. ) it is better to seek help from a lawyer who will quickly calculate the penalty correctly and save significant time.

Examples of calculating the amount of the penalty at the refinancing rate

In the first case (when penalties are specified in the contract), the calculation can be clearly shown using the following example.

Under the purchase and sale agreement, a citizen (buyer) purchased building materials with a total cost of 15 thousand rubles, including delivery from a certain company (supplier).

The supplier under the contract agreed to deliver this product within 5 days from the date of payment. The company did not fulfill its obligation on time and, in addition, the delivery was already a whole week late.

The parties stipulated that if the supplier delays delivery of goods, the buyer will have the right to demand payment of a penalty for each day of delay in delivery of goods in the amount of 1% of the contract price.

Thus, the following indicators are obtained:

  • contract price – 15 thousand rubles;
  • percentage rate – 1% (in the formula, for simplification, you can immediately use 0.01);
  • the period of delay is 7 days.

They add up to the following calculation: 15,000 * 0.01 * 7 = 1,050 rubles per week of delay.

In the second case, using the bank rate of the Central Bank of the Russian Federation, an example with the following parameters will be considered.

  1. It is necessary to repay the debt in the amount of 1,000,000 rubles.
  2. The delay is 45 days.
  3. Refinancing rate from January 1, 2016 equal to 11% per annum (in the formula, for simplification, the number 0.11 will be used).

The refinancing rate of the Central Bank of the Russian Federation (re-financing) is the minimum interest rate on the loan that the Central Bank issues to commercial banks. This rate is also used when calculating the taxable amount of deposits in commercial banks, when accounting for and settling bills and other securities. In some cases, the refinancing rate may be changed (due to the macroeconomic situation and the level of development of the national economy). Also, the refinancing rate is the basis of the taxation system.

Calculation of interest at the refinancing rate

When borrowing money, you need to understand that you will have to pay interest for using the money. Any interest on loans and borrowings is based on the refinancing rate.

There are loans for which the interest is equal to the refinancing rate, but more often commercial banks issue loans at a higher interest rate, taking into account the refinancing rate (at which a commercial bank borrows from the Central Bank), risks and additional profit of the bank.

Interest on deposits (bank deposits) is also calculated at the refinancing rate. Based on this rate, you can find the interest on the deposit on which tax will be charged. The tax is 35% of interest on deposits exceeding 13.25% (refinancing rate 8.25% + 5%).

Interest equal to the refinancing rate is also paid by the employer if there is a delay in paying wages to staff.

Calculation of penalties at the refinancing rate

Penalty is the amount paid for a penalty. The penalty is prescribed in the contract as an emergency measure in case of failure to repay the debt on time. The penalty is measured as a percentage of the amount of the monetary obligation, calculated for a specific period (usually per day). Most often, the terms of the penalty are specified in the contract. If such conditions are not specified in the contract, relations between the parties to the contract are regulated in accordance with Article 395 of the Civil Code.

The penalty is calculated daily, starting from the day following the payment due date and is equal to the current refinancing rate. The refinancing rate, set by the Central Bank at 8.25%, has not changed since September 2012. The refinancing rate can be found on the official website of the Central Bank of the Russian Federation.

Formula for calculating penalties at the refinancing rate

Exists two basic formulas for calculating penalties at refinancing rate:

Formula 1: P=C*D*(i/(100*300)),

P – amount of penalty;

i/300 – in accordance with the instructions of the Bank of Russia, 1/300 of the current refinancing rate is accepted;

Formula 2: P=C*(D/360)*(i/100),

where P is the amount of the penalty;

D – payment amount for the period of delay;

C – period of non-payment of payment in days. The number of days of non-payment is calculated based on the day following the payment date.

i – current refinancing rate of the Central Bank;

360 – number of days in the financial year.

Calculation of tax penalties

Penalties for taxes and fees are accrued only in case of untimely payment of the tax burden (failed to meet the deadline). If a tax payment is late, in addition to penalties, other measures may be applied to the defaulter to ensure payment.

P=C*D*(i/(300*100)),

P – amount of penalty;

D – payment amount for the period of delay;

C – period of non-payment of payment in days. The number of days of non-payment is calculated based on the day following the payment date;

i/300 – in accordance with the instructions of the Bank of Russia, 1/300 of the current refinancing rate is accepted.

Calculation of penalties at the refinancing rate for an arbitration court

The official website of the Arbitration Court (SAC RF) presents a methodology for calculating penalties at the refinancing rate. To calculate the penalty, the following data must be taken into account:

  • amount of debt including VAT (the full amount under the agreement including taxes is indicated. In the case of this, the amount of funds specified in the agreement is indicated);
  • period of delay “from” and “to” (the number of days is calculated from the day following the payment due date);
  • VAT (a tax rate of 18% or 10% is indicated depending on the regime. If no tax is provided, it is set to 0);
  • refinancing rate (the current refinancing rate is indicated).

The calculation of interest at the refinancing rate is based on the legal position set out in the Resolution of the Presidium of the Supreme Arbitration Court of the Russian Federation dated No. 5451/09 of September 22, 2009.

Penalties at the refinancing rate for the arbitration court are calculated using the following formula:

Penalty for the period = (Amount of debt*Number of days of non-payment*Refinancing rate)/36000.

If the refinancing rate changes within the period of non-payment, it is necessary to calculate the penalty for each part of the period separately.

Example of penalty calculation

For example, the amount of debt is 100,000 rubles, the due date for payment is November 25. The payment was overdue until December 5th. The current refinancing rate is 8.25%. VAT is not charged.

Then the period of late payment begins from November 26 and is 10 days until December 5.

Then the penalty will be:

P=10*100000*(8.25/(100*300))=275 rubles;

P=10*(100000/360)*8.25/100=229.17 kopecks.

In the first case, the amount of debt, including penalties, will be 100,275 rubles, in the second - 100,229.17 rubles. Thus, it is more profitable to calculate the penalty using a formula taking into account the length of the financial year (360 days).