The ZEK entry is the most important data record a bank sees about you when you apply for a loan in Switzerland. The Central Office for Credit Information (ZEK) records active contracts, rejections, and your payment behaviour – and thereby largely determines whether your loan application is approved or rejected. In this guide you'll learn exactly what is recorded, how long entries remain on file, and what the difference is between ZEK and IKO.
What is the ZEK?
The Central Office for Credit Information (ZEK) is a private-law association based in Zurich. Its members – banks, leasing companies, and credit card providers – voluntarily report data on consumer loans, leasing contracts, credit cards, and current-account credit. The ZEK was created to warn lenders of over-indebtedness situations and to detect multiple debt exposure at an early stage.
Important: the ZEK is not the same as the IKO – although in practice almost everyone speaks of a “ZEK entry” when they actually mean the legally mandated IKO notification. More on this in the section “ZEK and IKO – the difference”.
What does the ZEK record?
The ZEK records considerably more than just loan contracts. The following contract types are captured:
- Cash loans: personal loans, car loans, renovation loans
- Fixed-term credit: credit with a fixed term and no instalment repayment
- Leasing and rental contracts: car leasing, equipment leasing
- Instalment credit: instalment purchases in retail
- Current-account credit: overdraft limits on bank accounts
- Credit card exposures: card limits and outstanding balances
- Overdraft credit: account overdrafts
- Loan applications: open and rejected applications
- Official information: bankruptcies, composition proceedings, incapacity to act
In addition, the ZEK records a so-called flag for each contract, indicating whether it is a contract of another institution (code 0), the reporting branch's own contract (code 1), or another branch of the same institution's own contract (code 2). This lets the lender see immediately whether it already has a relationship with the customer.
The ZEK creditworthiness codes in detail
Every contract in the ZEK carries a creditworthiness code describing the customer's payment behaviour. This code is decisive for your next loan application:
- Code 0: no indication resp. good creditworthiness – Neutral
- Code 1: balance offset with a new loan (debt restructuring) – Positive
- Code 2: regular repayment – Positive
- Code 3: slow repayment – Negative
- Code 4: special measures / default under the KKG – Negative
- Code 5: partial or total loss (certificate of unpaid debt) – Negative
- Code 6: legal uncertainties – Negative
- Code 21: termination of a leasing contract – Negative
Codes 0, 1, and 2 are unproblematic – they show that a loan was serviced properly. From code 3 onward it becomes critical: slow repayment signals to the next bank that there were payment problems. Codes 4 and 5 (special measures and loss) are generally a knock-out criterion for new loan applications.
How long do ZEK entries stay on file?
Retention periods depend on the contract type and the creditworthiness code:
- Active contract: for the entire term of the contract
- Closed contract with a positive outcome (code 0, 1, 2): 3 years after closure
- Closed contract with partial/total loss (code 5): 5 years after closure
- Closed contract with legal uncertainties (code 6): 5 years after closure
- Rejected loan application: 2 years
- Open loan application: until the valid-until date (3–12 months)
In concrete terms, this means that even if you repaid a loan in full and on time, the entry remains visible in the ZEK for another 3 years – albeit with a positive creditworthiness code. A certificate of unpaid debt, on the other hand, burdens your profile for a full 5 years.
ZEK and IKO – the difference
In Switzerland everyone talks about a “ZEK check” – but hardly anyone knows that there are actually two separate systems:
- Legal basis: ZEK = private-law association (voluntary); IKO = legally mandated (KKG Art. 25–27)
- Scope: ZEK = all credit types incl. cards, current-account credit, loans above CHF 80,000; IKO = only KKG consumer loans (CHF 500–80,000, term >3 months)
- Retention after positive repayment: ZEK = 3 years; IKO = 14 days
- Retention after a negative event: ZEK = 5 years; IKO = 14 days
- Rejections recorded: ZEK = yes, 2 years; IKO = no
The IKO (Consumer Credit Information Office) is a legal obligation: every lender must submit an IKO notification for KKG-governed consumer loans and check the IKO before granting a loan. The ZEK, by contrast, is a voluntary association that records considerably more broadly and for longer.
The reason everyone still says “ZEK”: both systems are run by the same office in Zurich and technically operate over the same interface. In the banking software, only a single parameter is switched – and the query is then run for ZEK alone or for ZEK and IKO together.
For you as a consumer, the difference matters mainly for retention: with the IKO, your data is deleted 14 days after the contract ends. With the ZEK, it remains visible for another 3 years – and that is exactly the data the next bank sees.
What happens during a ZEK check?
When you submit a loan application, the following happens:
- Registering the loan application: the bank reports your loan application to the ZEK. From this moment, it is visible to other institutions that you have applied for a loan.
- Data comparison: the ZEK returns all information recorded about you to the bank – active contracts, previous contracts, rejections, creditworthiness codes, and open loan applications at other institutions.
- Approval or rejection: based on this data (and the budget calculation), the bank decides on your application.
- Contract or rejection notification: after the decision, the bank reports either the new contract or the rejection to the ZEK.
Automatic feedback notices (ARM)
A particularly important ZEK feature: if you have an active loan with one bank and submit a new loan application at another bank, your existing bank automatically receives an alert. These so-called ARMs (automatic feedback notices) inform the existing lender about new activity by its customer.
This has a far-reaching consequence: if you apply for loans at several banks simultaneously, all the institutions involved see the others' open applications. In the Swiss lending industry, this is regarded as a warning sign – the customer is classified as “desperate”. The result: rejection by all banks.
Tip: never apply for a loan at several banks at the same time. Instead, use a loan broker who deliberately selects a suitable bank and submits only a single application.
The ZEK rejection codes
If your loan application is rejected, a rejection code is recorded in the ZEK. The most common codes:
- Code 7: debt ratio too high
- Code 9: customer's information doubtful
- Code 10: customer waives the loan
- Code 13: requested credit amount too high
- Code 14: rejection for legal reasons
- Code 99: rejection without stating reasons
Code 99 – “rejection without reasons” – is in practice the most common. Banks are not obliged to state the exact reason. For the customer this is frustrating, since they don't know what went wrong.
Requesting a ZEK self-disclosure
Under data protection law, everyone has the right to request a free self-disclosure from the ZEK. The request is made in writing to the ZEK office in Zurich. You then receive an overview of all data recorded about you – active contracts, closed contracts, rejections, and creditworthiness codes.
It is advisable to check your own ZEK data before applying for a loan. Incorrect entries can be corrected via the lender that made the report. The ZEK itself cannot change entries on its own – this must always be done via the institution that originally submitted the notification.