Hybrid mortgage: how fixed-then-variable loans work

A hybrid mortgage — called a mixed mortgage in Spain and an ARM such as a 5/1, 7/1 or 10/1 in the US — combines a fixed rate for the first years with a variable rate for the rest of the term. It gives you certainty while your debt is highest and exposes you to rates once the balance is smaller. It works well if you understand what happens the day the fixed period ends.

• A fixed period (usually 3 to 15 years), then benchmark + margin until the end — in Europe the benchmark is usually 12-month Euribor.
• When the fixed period ends, the payment is recalculated on the outstanding balance and the remaining term.
• Nobody knows where rates will be in 10 years: decide with scenarios, not forecasts.
• It suits you if the variable payment would still be affordable with high rates.
• Compare it with a fixed loan by APR and by total interest across several scenarios.

How it works

During the fixed period you pay a rate agreed at signing, the same every month. After that, the loan becomes variable: your rate is the benchmark (for example, 12-month Euribor) plus a margin also agreed at signing, reviewed every 6 or 12 months until the end.

The fixed-period payment is calculated as if the loan lasted the whole term. When the variable period starts, the lender recalculates it with the new rate, on the principal you still owe and the months remaining.

A worked example

A €200,000 loan over 30 years: 10 years fixed at 2.4%, then Euribor + 0.5%.

• Payment for the first 10 years: €779.88.
• Balance owed when the fixed period ends: €148,536.

From then on, the payment depends on Euribor. If it stayed at each of these levels for the remaining 20 years:

What the example tells you

• With moderate rates, the hybrid is cheaper than a 3.0% fixed loan (€73,927 of interest vs €103,555).
• With Euribor at 4%, the payment rises to about €940 and the total cost exceeds the fixed loan.
• The payment jump is never as large as with a fully variable loan, because it comes after you have repaid about a quarter of the debt.

The key question: could you pay €940 a month in 10 years? If the answer is yes, with room to spare, a hybrid is reasonable. If not, a fixed rate protects you better.

How long to fix

• Short periods (3-5 years): lower initial rate, but exposure to rates comes early, on a still-high balance.
• Medium periods (7-10 years): the usual balance. They cover the years with the most debt and family expenses.
• Long periods (15 years or more): close to a fixed mortgage; the initial rate approaches the fixed rate.

A useful rule: fix at least the years in which the payment weighs most on your budget.

What to negotiate

• The fixed rate and the length of the fixed period.
• The margin for the variable period: it applies for the rest of the loan, so every tenth of a point matters.
• The review frequency (6 or 12 months) and, in the US, the rate caps per adjustment and over the life of the loan.
• Prepayment fees: during the fixed period they tend to resemble those of a fixed loan.

What to do as the fixed period ends

A year before, simulate the payment with the current rate and with a higher one. If you do not like the result, you have options:

• Prepay to reduce the balance that will move to the variable rate. See paying off your mortgage early.
• Negotiate a switch to fixed with your lender or move the mortgage to another one. See refinancing or renegotiating your mortgage.

Frequently asked questions

What happens when the fixed period of a hybrid mortgage ends?

The loan becomes variable: the lender recalculates the payment applying the benchmark plus the agreed margin to the remaining balance and term, and reviews it periodically.

Is a hybrid mortgage better than a fixed one?

A hybrid usually starts with a lower rate and can be cheaper if rates stay moderate. A fixed loan removes the risk. If a higher variable payment would strain your budget, fixed is more prudent.

How many fixed years should I choose?

Seven to ten years is the most common choice because it covers the period of highest debt. Shorter periods make the start cheaper but bring the risk forward.

Is a hybrid the same as a US ARM?

The idea is the same: an initial fixed period and then periodic adjustments. US ARMs add caps that limit each adjustment and the lifetime increase.