Fionnuala Earley, chief economist at Nationwide, said: “The answer to this puzzle lies in the different types of people who fall into the first-time buyer category. No longer can we think of first-time buyers as the fresh-faced young person, or couple, getting their very first foot on the housing ladder after saving hard for a deposit. Rather, the category includes a big proportion of buyers returning to the market, perhaps after a spell in rented accommodation or moving from dissolving households. In 2005, ‘returners’ may have accounted for one in five of all first-time buyers.”

House purchasers are classed as first-timers if they are not selling a property at the same time as they are buying. Therefore those who have sold up and rented for a while, for whatever reason, fall into this category.

The number of true first-time buyers — those who have never owned their own home before — is decreasing because they cannot afford to buy.

House prices have risen 89% over the past five years, according to Nationwide, and the average house price is now £164,632. This, coupled with the fact that an increasing number of young people are leaving university with large debts, means that the average age of first-timers is rising. Figures from the Council of Mortgage Lenders show it is 29, compared with 26 in 1980.

Added to that is the fact that many people are choosing not to buy until they are in their thirties because it does not suit their lifestyle and they prefer the flexibility of renting. A number of people also choose to sell up and go travelling for a few years before returning and getting on the property ladder. And the increasing number of divorces mean many people are forced to start again in the housing market.

Mark Chilton at Purely Mortgages, a broker, said: “The nature of first-time buyers is changing, and you do find that the circumstances tend to differ between the different groups.”

The under-thirties often have little or no deposit and many have to rely on help from their parents to get started. This group are therefore most likely to require specialist mortgage products such as 100% loans or deals that accept guarantors.

More lenders are offering schemes that have been specifically designed for those struggling to buy their own property. For example, with Bank of Ireland’s First Start scheme parents can take a joint mortgage with their son or daughter, but they do not jointly own the property. This enables the child to benefit from enhanced borrowing without a parent’s name having to be on the deeds.

However, the main drawback with these products is that the rates tend not to be the most competitive. To benefit from the best rates you really need a deposit of 10% or more. This is where older first-time buyers often have an advantage.

Melanie Bien at Savills Private Finance, another broker, said: “An increasing number of people with first-time-buyer status have actually owned property before. They tend to be older and often have some savings to put down as a deposit. In many cases the deposit is quite large because they have equity from their old home. This means they have a wider choice of loans available to them and can benefit from cheaper rates.”

The best two-year discount is from Ipswich building society at 4.15%. This compares with Bank of Ireland’s two-year discount on its First Start range, charging 5.09%.

The Ipswich deal requires only a 5% deposit but if you have less than 10% to put down you will have to pay a higher lending charge, which will make it less competitive. This is in effect an insurance policy that protects the lender if it has to repossess the property and is only able to sell it for less than the outstanding mortgage.

Divorced people often have a sizeable deposit to put down because of the money from the divorce settlement, but getting a mortgage can be difficult if your main source of income is maintenance payments.

Ray Boulger at John Charcol, a broker, said: “Maintenance income is a problem because most lenders will not take it into consideration. Some will if you have a court order, but if it has been an amicable split and all you have is a solicitor’s letter, only Yorkshire building society and Accord will include it. The way you can get round it is to go for a self-certification mortgage, because then you are not asked to prove your income. But you can do this only if you have a job as well, as you do have to give details of your employer.”