And more homeowners are worried by their mounting debts. One in six mortgage borrowers . . . and one in five of those with other borrowings on top . . . say their debt level is already a "significant concern".

And with at least two more, and maybe even three, rises expected before the end of the year, the outlook is not good. According to the study, an extra half percent on the cost of borrowing would put 80,000 home owners under "some strain", with 50,000 of them suffering "considerable strain".

The banks are not helping by using the drip-drip rise in interest rates as an excuse to boost their lending margins. It is a familiar trick that leads to borrowers getting hit with the full impact of higher interest rates while the deposit rates paid to many savers have hardly budged.

Demand deposits, which give savers immediate access to their cash, are the worst offenders. Even though the European Central Bank has raised interest rates by 0.75% since last November, none of the main banks or building societies pays anything close to this amount. Instead the most you can expect from your local bank or building society branch is a miserable 0.1%-0.3%.

With the banks sitting on deposits of 61bn, much of it earning little or no interest, savers have handed the financial institutions a licence to print money according to Diarmuid Kelly, chief executive of the Professional Insurance Brokers Association.

"The banking system is literally awash with cash invested in low-yielding deposit accounts, " he says "In an environment of rising inflation, the value of savings in banks is actually being eroded. Interest rates after tax are typically 2% or less while inflation is at 3%. The banks lend this money on for rates of up to 9%. If they make an average margin of just 4% on their lending, they are making almost 2.5bn per year from the 61bn sitting on deposit."

Mortgages account for a big chunk of the lending and, while few savers have seen the full benefits of higher interest rates, home owners have generally been stung for the full 0.75% hike by the ECB since November.

At first it looked like some of the bigger banks had decided to give borrowers a break, if only to boost their standing in the mortgage league tables.

After the ECB's first quarter point hike in December, Permanent TSB, Bank of Ireland and AIB held back some of the increase from their mortgage customers.

Permanent TSB repeated the trick when rates moved again in March, transforming its position from having one of the highest standard variable mortgage rates to one of the most competitive.

But the giveaways are well and truly over and all lenders without exception have passed on the ECB's latest quarter point rate rise in full to borrowers on the standard variable rate. Now that the dust has settled, the market has settled into three price brackets.

Bank of Scotland, AIB and EBS have the lowest standard rates at 4% variable (see table). Permanent TSB and IIB Homeloans rank mid table while all of the other lenders hover around 4.24%.

The gap between the top and bottom of the table might not look like a lot but, based on today's telephone number mortgages, even small rate differentials can add up to big savings.

For example, the payments on a 300,000, 25-year mortgage work out at just under 1,600 a month if you borrow from Bank of Scotland. But if you borrow from First Active, which has the highest standard variable rate on the market, the payments on the exact same mortgage rise to almost 1,650. That's an extra 600 over the course of a year.

But rather than switching between standard variable rates, consider moving to a tracker mortgage instead.

These shadow the ECB by a fixed margin and are generally much better value than lenders' standard rates. For example, if your mortgage is worth less than 80% of the value of your home, National Irish Bank will switch you to a tracker mortgage at 3.74% interest.

That is a full half percent lower than what most people pay on a standard variable rate, resulting in savings of almost 85 a month or more than 1,000 over the course of a year.

Unless you were lucky enough to lock into a low fixed-rate mortgage while they were still available, there is no way to completely avoid the upward climb in interest rates. But you can ease the pain by switching from an overpriced standard variable rate.