When is a loan extension necessary?
When you take out a loan from a lending institution such as a bank, there is usually a fixed-interest period, for example for ten years. This means you must pay the agreed interest rate for precisely those ten years and it does not change during that period. Even if the same lender were to offer a better rate, the fixed-interest period remains in effect for the agreed duration.
This is a common practice by lenders, as it guarantees them a predictable amount from the outset. The borrower thereby commits, as in our example, to regularly pay a certain amount to that lender for ten years. With this amount, they both repay the loan and, of course, pay the lender the amount charged. After, taking our example, ten years, this amount is paid off.
If the borrowed sum is not yet repaid at the end of the fixed-interest period, a loan extension is necessary. In principle there are two options: an extension with the existing lender or a debt restructuring.

Starting point for a loan extension
In most cases the loan is not fully repaid by the bank at the end of the fixed-interest period; often it is not even half of the loan amount. When this occurs, the lender and the borrower negotiate a extension of the loan agreement with new terms. Shortly before the old loan agreement expires, you should consider a so-called loan extension.
Whether a loan extension makes sense and how such an extension works are among the important points you should consider in advance. Generally, some time before the end of the fixed-interest period you will receive a letter from your lender. This includes the new terms of the contract as well as a possible new fixed-interest period for follow-up financing. This is called a prolongation or a prolongation offer. You are not obliged to accept this loan extension, however. A prolongation is thus a follow-up financing.
Debt restructuring instead of a loan extension?
There is another possibility. Since the lender continues to assert its claim against the borrower, the only alternative to a loan extension is a debt restructuring. Everyone is free to choose a new lender. That lender simply has to agree to the contract terms, as does the borrower.
So you have to take out a new loan in a certain way, but usually the same or perhaps better conditions apply to the borrower, depending on what has been negotiated. Such a process is no longer called a loan extension but is referred to as debt restructuring.
However, if you can and want to stay with your current conditions, or even received an attractive offer from your chosen lender such as a bank, you are of course free to carry out the loan extension with the familiar institution.

Loan extension terms
In any case, a loan extension saves the borrower a lot of time that would otherwise be needed for new loan processing and potentially for changes in the land register. In addition, the installments become smaller if the term is set longer.
Of course it also depends on what you want to finance. For smaller consumer loans, for example to finance furniture for the kitchen, bathroom or similar, a "normal" financing period is about 12–36 months. A car can already be financed from 36 months.
There are, of course, shorter terms here as well, but you must bear in mind that the installments must be affordable alongside other ongoing costs. Financing an apartment or even a house, on the other hand, can take up to 25 years. Paying lower interest rates when extending the loan can therefore be an attractive offer, especially for long-term financing.
Loan extension vs. debt restructuring

Contrary to many assumptions, the fixed-interest period applies only to the borrower. The lender is free to adjust the rate or even demand immediate repayment of the remaining balance. Some reasons for this can be a reduction in the borrower's income, family growth, a divorce or even a long-term sick leave.
A new lender, such as a bank, is of course cautious in the face of such life changes of a borrower. It could be that the borrower had the outstanding balance restructured because long-term sick leave makes unemployment likely. A lender, after all, is concerned about its money.
If, however, the loan is extended with the original lender, there is already a longer relationship and the lender might reconsider demanding the total amount (the outstanding balance). Or the lender knows the circumstances and refrains from increasing the interest rate from the outset, because they know the borrower can only afford the financing that way. After all, the lender earns steadily from this.
Moreover, after a long fixed-interest period and a subsequent loan extension, most lenders are willing to accept a repayment in unspecified amounts. A new lender is generally less inclined to accept such a repayment offer, or may even reject it outright. Naturally, the interest rate for a loan extension is then adjusted to the current market, but the borrower must also expect new, usually higher, rates in the case of debt restructuring.
You should also not always rely on your house bank for a loan extension. Often the house bank offers a worse deal than other providers.
Quick repayment
Of course everyone wants to repay their loan as quickly as possible to the respective lending institution. After all, you want to be able to call the financed item your own and use your money elsewhere again. However, if further financing is required or it is a long-term loan, such as for a house, a loan extension is quite advisable. You are familiar with the lender and can therefore expect, in some cases, better terms and more consideration from them than from a new, unknown lender. Time and costs for changes in the land register are also eliminated, and the other points mentioned above show that a loan extension is often the right choice.
Only rarely can one advise a debt restructuring. With a loan extension, a borrower is usually better advised.
In any case, several debt restructuring offers should be obtained before the end of the fixed-interest period. These can form a good basis for negotiation when it comes to a loan extension. You will also have the good feeling of having weighed all options.