How to Calculate SSK and SGK Delay Surcharge? In the Turkish tax system, the concepts of “delay surcharge” (gecikme zammı) and “delay interest” (gecikme faizi) are sometimes confused. That confusion can lead to disputes between tax authorities and taxpayers. These measures are not punitive fines in the criminal sense; they are financial adjustments applied to taxes and public receivables that were established late or not paid on time. Below we explain the legal basis, calculation method, and differences between delay surcharge and delay interest. Note that when the delay surcharge rate is adjusted, related rates such as delay interest and voluntary disclosure surcharges are also affected—so a single change can produce three distinct increases.
What Is the Delay Surcharge?
The delay surcharge is applied when public receivables are not paid on time. The definition of public receivable is provided in Article 51 of Law No. 6183 on the Procedure for the Collection of Public Receivables. In everyday speech people often call these amounts “interest,” and the terms may be mixed up. However, from a tax law perspective, interest and surcharge are distinct concepts.
A simple distinction is:
- Delay interest is applied to public receivables that have not yet been assessed,
- Delay surcharge is applied to due but unpaid public receivables.
The statutory delay surcharge rate is applied separately for each month of nonpayment. Traditionally this was set at 2.5% per month for unpaid tax debts and similar public receivables such as SGK premiums. The surcharge is a monthly penalty equal to that percentage of the outstanding balance for each month of delay. It is calculated not only on the unpaid tax itself but also on penalties imposed for tax loss (tax ziyaı) or other fines related to the unpaid amounts. Tax loss penalties are typically equal to the lost tax amount (onefold), and in cases such as use of fake invoices (naylon fatura) the penalty can be threefold.
How the Delay Surcharge Is Applied
Under Article 51 of the Law on the Procedure for the Collection of Public Receivables, a delay surcharge is applied to the unpaid portion of a public receivable from the day after the due date. The surcharge is calculated separately for each month; fractions of a month are calculated on a daily basis.
The minimum delay surcharge is set at one Turkish Lira.
- For tax loss penalties imposed under the Tax Procedure Law, the delay surcharge is applied at the rate specified in Article 51. For public receivables that are judicially determined as penalties, the surcharge is applied at half of the prescribed rate. Delay surcharge is not applied to other kinds of punitive public receivables that are outside these rules.
- The Council of Ministers has authority to reduce monthly surcharge rates in bulk or for specific months down to 10%, to increase the surcharge rate and minimum amount up to twice, to vary rates by month, and to allow compound calculation of surcharges on a monthly, quarterly, semiannual, or annual basis.
- Article 52 governs the suspension of surcharge accrual in certain situations. If a public receivable has been deferred (tecil), if bankruptcy proceedings have been opened, or if the debtor has been declared insolvent, surcharge accrual is suspended for the relevant period. This protects debtors whose control over assets has been removed through no fault of their own.
- There is no requirement to notify the debtor in advance about the delay surcharge. Payment of the principal public receivable does not prevent follow-up or collection of the accrued surcharge.
What Is the Current Delay Surcharge Rate?
As of the Presidential Decree dated October 1, 2019 (published October 2, 2019), the monthly delay surcharge rate specified in Article 51 of Law No. 6183 was revised from 2.5% to 2.0% per month. That change reduced the rate that had been in effect since July 1, 2019.
What Is Delay Interest?
Delay interest is defined under Article 112/3 of the Tax Procedure Law. It applies to assessments made by way of completion, ex officio, or administrative reassessment. For taxes that have become final without litigation, delay interest is calculated from the normal due date for the tax period until the date of the final reassessment. For taxes that are subject to litigation, delay interest applies from the due date for the relevant period until the date the court decision is notified. The rate used is the delay surcharge rate determined under Law No. 6183.
Delay interest is paid within the same timeframe as the related liability, and partial-month periods are not taken into account when calculating interest. Delay interest is also involved in the computation of tax loss penalties. Under Article 344 of the Tax Procedure Law, the tax loss offense arises when a taxpayer or responsible party causes loss under the conditions listed in Article 341. The penalty for tax loss is generally equal to the lost tax amount; for the period from the normal due date to the date the penalty notice is issued, half of the delay interest calculated on the lost tax amount (as set out in Article 112) is added to the penalty.
How the Delay Interest Is Applied
Under Article 112 of the Tax Procedure Law, for assessments made by completion, ex officio, or administrative means:
- For taxes that are final without litigation: delay interest is applied from the normal due date for the period until the date the last assessment is accrued,
- For taxes under litigation: delay interest is applied to the unpaid portion from the normal due date until the date the judicial decision is notified,
- The delay interest rate used is the rate determined under Law No. 6183, and interest is paid within the same period. Partial months are not considered in interest calculation.
- Where taxes are settled by agreement either before or after assessment, delay interest is applied to the agreed tax for the period from the normal due date to the date the settlement record is signed, at the delay surcharge rate.
Because many cases and Court of Appeals (Danıştay) decisions relate to disputes arising during reconciliation and assessment processes, care is required when calculating delay interest in reassessment and settlement contexts.
What Is the Current Delay Interest Rate?
Since delay interest is applied at the same rate as the delay surcharge, the Presidential Decree No. 1592 dated October 1, 2019 also changed the delay interest rate to 2.0% per month, effective from October 2, 2019.